Claims:1. An oral liquid, pharmaceutical composition comprising Isotretinoin or pharmaceutically acceptable salts thereof, a phospholipid carrier and other pharmaceutically acceptable excipients.
2. The oral liquid pharmaceutical composition according to claim 1, wherein the said liquid composition is a pharmaceutical solution.
3. The oral liquid pharmaceutical composition according to claim 1 wherein Isotretinoin or salts thereof comprises between 0.1 % to 7.0 % by weight of the composition.
4. The oral liquid pharmaceutical composition according to claim 1 wherein said phospholipid carrier comprises of phosphatidylcholine from natural sources such as soybean and egg or synthetic phosphatidylcholine and combinations thereof.
5. The oral liquid pharmaceutical composition according to claim 4 wherein said phosphatidylcholineis dissolved in a suitable vehicle/ carrier system.
6. The oral liquid pharmaceutical composition according to claim 4, wherein the phospholipid present in the composition ranges from 0.5% to about 80% by weight of the composition.
7. The oral liquid pharmaceutical composition according to claim 1, wherein the phospholipid carrier further comprises of lipophilic solvents, hydrophilic solvents, emulsifying agents and combinations thereof.
8. The oral liquid pharmaceutical composition according to claim 1 further comprising one or more pharmaceutically acceptable excipients selected from one or more of surfactants, antioxidants, chelating agents, preservatives, colors, sweeteners and flavors and mixtures thereof.
9. The oral liquid pharmaceutical composition according to claim 6 wherein the lipophilic carrier comprises of fatty acid esters, fatty acids, vegetable oils and mixtures thereof.
10. The oral liquid pharmaceutical composition according to claim 7 wherein said the emulsifiers and surfactants comprises fatty acids, mono and diglycerides, sorbitan fatty acid esters, polysorbate derivatives, polyoxyethylene sorbitan fatty acid esters, polyethoxylated castor oils, polyoxyethylene glycol glycerides, propylene glycol esters, fatty acid glycerol esters, vitamin E TPGS, sodium lauryl sulphate, dioctyl sodium sulfosuccinate, poloxamers and mixtures thereof.
11. The oral liquid pharmaceutical composition according to claim 7 wherein said the emulsifiers and surfactants comprises between 1.5% to about 60% of the composition.
12. The oral liquid pharmaceutical composition according to claim 6 wherein saidthe hydrophilic solvent comprises monohydric alcohols, glycols, polyols, glycerol, and combinations thereof.
13. The oral liquid pharmaceutical composition according to claim 6 wherein hydrophilic solvent comprises between 0.5% to 50% of the composition.
14. The oral liquid pharmaceutical composition according to claim 7 wherein said composition comprises of antioxidants selecting from the group consisting of butylated hydroxy toluene, butylated hydroxy anisole, ascorbyl palmitate, propyl gallate, tocopherol and combinations thereof.
15. The oral liquid pharmaceutical composition according to claim 7 wherein said the chelating agents comprises disodium edetate, calcium disodium edetate and combinations thereof.
, Description:THE PATENTS ACT 1970
(39 Of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)

1. Title of the Invention
ORAL LIQUID PHARMACEUTICAL COMPOSITIONS OF ISOTRETINOIN

2. Applicant (s)
(a) Name : IDRS Labs Private Limited
(b) Nationality : Indian
(c) Address : #235-H, Phase 3, Bommasandra Industrial Area,
Hosur Road, Bangalore – 560099.
India.
Phone numbers: (+91) (80) 4545-9595
Email: info@idrslabs.com
3. Preamble to the Description
The following specification particularly describes the invention and the manner in which it is to be performed.

Technical Field of the Invention
This invention relates to an oral pharmaceutical liquid dosage form of Isotretinoin or salts thereof in the form of a solution. The present invention further relates to the processes for preparation of such compositions.
Background of the Invention
Isotretinoin (ISA) as known as 13-cis retinoic acid is a Vitamin A derivative. Isotretinoin, its isomers and other analogs show therapeutic efficacy in severe dermatological disorders such as cystic acne, cutaneous lupus erythematosus, psoriasis and keratinization disorders.
Isotretinoin received FDA approval in 1982 for severe recalcitrant acne under the brand name ACCUTANE®marketed by Hoffman La Roche as a suspension of Isotretinoin encapsulated in soft gelatin capsule dosage form. Later, Sun Pharmaceuticals received approval for a hard gelatin capsule, using patented Lidose® technology with enhanced bioavailability, under the brand name ABSORICA®.The recommended dose of Isotretinoin is 0.5 to 1 mg/kg/day given in two divided doses with or without meals for 15 to 20 weeks. ABSORICA LD®which received approval in 2019 is a low dose formulation with recommended dose of 0.4 to 0.8 mg/kg/day given in two divided doses with or without meals for 15 to 20 weeks.
Isotretinoin is known to modulate cell growth, induce cell differentiation as well as apoptosis and hence has proven efficacious against various cancers such as skin cancers, cutaneous T-cell lymphoma, acute promyelocytic leukemia, lung cancer, breast cancer, ovarian cancer, bladder cancer, kidney cancer, head and neck cancerswhen used alone or in combination.
Isotretinoin (ISA) is used to treat neuroblastoma, the most common type of extracranial solid tumor in children. Neuroblastomas comprise 97% of the total sympathetic nervous system cancers and represents 7.8% of cancer in children younger than 15 years of age.Because of the aggressive nature and high likelihood of metastatic disease at diagnosis, neuroblastoma accounts for nearly 15% of all pediatric cancer fatalities. Treatment with isotretinoin in high risk neuroblastoma reduces recurrence after high dose chemotherapy and stem cell transplant. Isotretinoin is given along with immunotherapy during the maintenance phase of the therapy.
Isotretinoin therapy is recommended for around 6 months for the condition where it is taken twice a day for two weeks followed by two weeks off the medication.
As is evident fromvarious studies isotretinoin therapy is prescribed for pediatric as well as adults including geriatric patients. Oral route is the preferred mode of administration of therapeutics. However, pediatric patients especially the ones below 10 years often find it difficult to swallow solid dosage forms such as tablets and capsules.Several barriers exist for children in swallowing capsules including anxiety, strong gag reflex, texture, size, and shape of capsule (Katherine K. Matthay, MD., Targeted Isotretinoin in Neuroblastoma: Kinetics, Genetics or Absorption, Clin Cancer Res. 2013 Jan 15; 19(2): 311-313).Children who fear swallowing capsules are likely to be tense when attempting to do so, therefore making the process more difficult. This tension, particularly in the throat, neck and chest can make the child feel like they are having trouble breathing which may cause further anxiety. Children who are fussy eaters or who gag frequently on food and drink can often struggle with swallowing medicines(strong gag reflex). Further, the texture, size, shape of the capsule, and the nature of the coating can affect the ease of swallowing for children.
Further, pediatric patients often need lower doses to be administered based on the body weight and body surface area which is difficult to achieve with tablets or capsules. Cutting, crushing, or manipulating tablets or capsules to achieve pediatric doses may result in inaccurate dosing, potentially leading to increased adverse effects or decreased effectiveness. The same problems can result from rounding each dose to the nearest tablet or capsule.
Preclinical and clinical studies have suggested that maintenance of adequate ISA plasma levels is crucial to drug activity (Reynolds et al. Response of neuroblastoma to retinoic acid in vitro and in vivo. Prog Clin Biol Res. 1991; 366:203–11). Vel’s et al attempted to examine potential factors that might affect achieving the target plasma level of Isotretinoin= 2 µMincluding clinical features, dose regimen, metabolism, pharmacogenetics and mode of administration.Young children, who were unable to swallow capsules,were administered Isotretinoin after cutting the capsules, extracting out the contents and mixing the drug either with soft foods before oral administration or directly administering via nasogastric tube. 92.5% patients who were able to swallow the capsules achieved the target Cmax as compared to only 55% of those who extracted the drug and mixed it with food or gave it via nasogastric tube. Thus, the lack of an age appropriate formulation clearly had a detrimental effect on the attainable plasma levels of Isotretinoin (Katherine K. Matthay, MD., Targeted isotretinoin in neuroblastoma: Kinetics, Genetics or Absorption, Clin Cancer Res. 2013 Jan 15; 19(2): 311–313).Therefore to achieve accurate and flexible dosing, improved therapeutic outcome, enhanced patient compliance especially for patients suffering from dysphagia i.edifficulty in swallowing and for administration via the nasogastric tube, an oral liquid dosage form is preferred.
Oral liquid dosage forms are homogenous mixtures where the active ingredient/s is either dissolved or suspended in a suitable vehicle or carrier. They offer advantages over solid oral dosage forms such as tablets and capsules in terms of providing flexible dosing based on body weight or body surface area, better patient compliance, suitability for pediatric and geriatric populations.Further,these dosage forms provide faster onset of action aswell as more reproducible bioavailability.
Solutions are liquid dosage forms where the active ingredient is dissolved in a suitable vehicle resulting in a monophasic system. Solutions offer advantages over other liquid dosage forms as it results in accuracy of dosage as phase separation is not an issue. Further, the onset of action is faster and it minimizes inter subject pharmacokinetic variability which is desired in highly variable molecules such as isotretinoin.
U.S. Pat. No. 9,078,925 discloses an oral pharmaceutical composition comprising Isotretinoin, lipophilic carrier comprises fatty acid esters (polyol ester of medium chain fatty acid selected from esters and mixed esters of glycerol, propylene glycol, polyglycerol and polyethylene glycol with medium chain fatty acids), fatty acids (C6 -C20 saturated, mono, di-unsaturated acid) fatty alcohols (C6 -C20 saturated, mono, di-unsaturated alcohol), vegetable oil (kernel oil, almond oil, groundnut oil, olive oil, soybean oil, safflower oil, sunflower oil , palm oil, sesame oil, canola oil or corn oil) and hydrophilic carrier (monohydric alcohols, glycols, polyols, glycerols).
U.S. Pat. No. 9,999,606 demonstrates the higher bioavailability of an oral pharmaceutical composition of Isotretinoin over a capsule comprising a semi-solid suspension of Isotretinoin. Isotretinoin is in the form of gel, dispersion, suspension or emulsion is adsorbed onto a carrier substrate selected from the group consisting of lactose, microcrystalline cellulose, calcium phosphate, dextrin, dextrose, sucrose, mannitol, maltodextrin and sodium aluminosilicate to form solid particles, powder, or granules.
U.S. Pat. No. 8,367,102 discloses an oral pharmaceutical composition of Isotretinoin for the treatment of acne, hypertrophic lupus erythematosus, basal cell carcinoma and squamous cell carcinoma which comprises a semi-solid preparation containing at least two lipidic excipients, at least one of them being hydrophilic having a Hydrophobic Lipidic Balance (HLB) value equal to or greater than 10, the other being an oily vehicle, whereby the at least one hydrophilic lipidic excipient(s) with a HLB value of at least 10 is selected from the group consisting of glycerol macrogolglycerides.
US 7,781,489 disclose a water-in-oil microemulsion comprising of Isotretinoin as an active ingredient, a phospholipid emulsifier, and sodium hyaluronate, wherein: the phospholipid emulsifier is phosphatidylcholine or soya lecithin.
US 2018318245 disclose a pharmaceutical composition comprising Isotretinoin, PEG 400, methyl paraben, propyl paraben, PEG 4000, and BHT wherein the pharmaceutical composition is formulated as a gel, ointment, lotion, emulsion, or cream.
US 6740337B2 disclose a bioavailable capsule composition of Isotretinoin.
WO 0000179 A1 disclose a solid dispersed preparation for poorly water-soluble drugs prepared by dissolving or dispersing the drugs in an oil, a fatty acid or a mixture thereof, mixing the solution or dispersion in a water-soluble polyol matrix and drying the mixture.
U.S. Patent Nos. 7,435,427 disclose capsules comprising a semi-solid suspension of isotretinoin containing at least two lipidic excipients, one having an HLB value equal to or greater than 10 and the other being an oily vehicle.
Isotretinoin is a highly lipophilic molecule which is practically insoluble in water and is highly sensitive to light and oxygen. Further, isotretinoin undergoes reversible isomeric conversion which can have an impact on the assay of isotretinoin in the formulation. Owing to these issues it is very difficult to formulate a solution form of the molecule. Further, there is no oral solution dosage form of Isotretinoin available in the market currently.
The present invention discloses a stable oral liquid dosage form of Isotretinoin solubilized in a phospholipid carrier leading to a solution form that can provide accurate and flexible dosingcombined with desired therapeutic effects. Further, the composition is in a concentrated form where the required dose can be delivered in small volumes which is desirablefor patient compliance. Further, the compositions can be administered as such or mixed with milk, water and /or soft foods before administration.
Summary of the Invention
In one embodiment, the present invention relates to a stable oral liquid pharmaceutical composition of 13-cis retinoic acid, also known as Isotretinoin for the treatment of various disease conditions.
In another embodiment, the present invention relates to a process for the attainment of an oral liquid pharmaceutical composition of Isotretinoin in the form of a solution in which high concentration of drug can be incorporated.
In one embodiment, the present invention discloses Isotretinoin containing pharmaceutical compositions which can be administered in low volumes to achieve the recommended therapeutic dose, provide flexible and accurate dosing, ease of handling and administration in addition to protecting the caregiver from exposure to the drug.
In another embodiment, the present invention relates to the flexible-dose oral liquid pharmaceutical composition of Isotretinoin presented in solution form to minimize variations in blood levels, enhanced bioavailability and better safety profile.
In one implementation, the oral pharmaceutically acceptable composition of Isotretinoin is in the form of a solution.
In a specific implementation, the stable oral liquid pharmaceutical composition includes
a) Therapeutically effective amount of Isotretinoin
b) a phospholipid carrier system and
c) at least one pharmaceutically acceptable excipient
In one embodiment of the invention the phospholipids are derived from soybean, eggs or are synthetic in nature.
In another embodiment of the invention the phospholipid is, but not limited to, phosphatidylcholine dissolved in a suitable solvent system which is composed of lipophilic carrier, hydrophilic carrier, emulsifying agents and mixtures thereof.
In another implementation, the compositions may further include surfactants, antioxidants, chelating agents, sweeteners, flavors, preservatives, colors and mixtures thereof.
In one implementation the pharmaceutical compositions of the present invention can be further filled in to capsules directly or after adsorbing it on a suitable solid carrier.
In one implementation, the disclosed pharmaceutical composition can be administered orally as such or after mixing with water, milk, and/or soft foods such as ice cream, pudding, whipped cream, oatmeal, yogurt etc. prior to administration.
In one implementation, the present inventors now recognize that the disclosed pharmaceutical composition of Isotretinoin is suitable for administration via the nasogastric tube in hospitalized patients unable to take the medication orally.
In one implementation, a method of treating Severe Acne Vulgaris, Severe Recalcitrant Nodular Acne, Alzheimer's Disease, Seborrhea, Recurrent Glioblastoma Multiforme (GBM), cervical cancers, Advanced Kidney Cancer, Embryonal Tumors of the Central Nervous System, T-Cell Malignancies, Multiple Myeloma, Malignant Glioma, Relapsed or Refractory Solid Tumors, High-Risk Neuroblastoma,, Acute Myeloid Leukemia, Myelodysplastic Syndrome, or Acute Lymphocytic Leukemia, Head and Neck Cancer and other off-label indications of isotretinoin, by administering an oral liquid pharmaceutical composition of Isotretinoin, comprising of drug solubilized in a phospholipid carrier solution and optionally pharmaceutically acceptable excipients.
Other objects, features, and advantages of the present invention will become apparent upon consideration of the following detailed description.

Detailed Description of the Invention
The present invention relates to a stable oral liquid pharmaceutical composition comprising Isotretinoin or salts thereof in solution form which provides flexible and accurate dosing. The process of preparation of these compositions is also provided.
It should be noted that the liquid pharmaceutical compositions according to the invention is a clear solution of Isotretinoin or salts thereof solubilized in a phospholipid carrier and suitable pharmaceutically acceptable excipients.
The present oral composition of Isotretinoin in the form of solution form has the advantage over previously marketed oral compositions of Isotretinoin known in the state of the art of having greater flexibility, which allows more accurately adjusting the dose of Isotretinoin to the needs of the patient.
By “solution” it is meant a clear liquid in which a solute is completely dissolved in a solvent to form a molecularly dispersed system. The solute of this invention is primarily Isotretinoin or salts thereof and the solvent is a phospholipid carrier solution more preferably phosphatidylcholine-basedcarrier system likes PHOSAL®.
The term “stable” used herein refers to the composition of Isotretinoinin solution form which is physically stable and the isotretinoin does not precipitate during storage. The compositions are also stable to oxidation and degradation during storage at recommended storage conditions.
The term “phospholipid carrier” refers to phospholipid molecules in a composition as a carrier solution. Such molecules may be identical to, or different from, each other. In other words, a phospholipid component may comprise a single phospholipid or comprise a mixture of two or more different phospholipids.
It was found that the liquid composition comprising Isotretinoin dissolved in phospholipid carrier preferably in a phospholipid solution shows enhanced solubility and stability.
The content of Isotretinoin or a physiologically acceptable salt thereof contained in the pharmaceutical composition of the present invention is generally about 0.1-7% by weight, preferably about 0.25to 6.5% by weight (as the converted amount to free Isotretinoin) relative to the weight of the composition.
Various lecithin or phospholipid solutions in a suitable vehicle comprising of alipophilic carrier alone or in combination with hydrophilic carriers may be used in the present oral liquid compositions of Isotretinoin.
Phospholipids (PL) are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group, and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue. The phosphate group can be modified with simple organic molecules such as choline, ethanolamine or serine.Variousphospholipids from plant and animal sources such as soybean phosphatidylcholine, egg phosphatidylcholine, or synthetic phosphatidylcholine, as well as hydrogenated phosphatidylcholine, are commonly used in different types of formulations. Phospholipids, either alone or mixed with various solvents, can be used as the final ingredient of the formulations mentioned above. These lecithin ingredients can include, for example, Alcolec. range of lecithin, produced by the American Lecithin Company, Phospholipon®90 and various types of PHOSAL® produced by Lipoid GmbH, Germany which constitute phosphatidylcholine with medium chained triglycerides (Phosal®25, 50 & 53 MCT), with propylene glycol (Phosal 50 PG),with safflower oil (Phosal® 50SA+)with sunflower seed oil (Phosal® 40 IP) and Lipoid®PPL-600 (soybean phospholipid in soybean oil and medium-chain triglycerides).
The concentration of the phospholipidspresents in the composition ranges from about 0.5% to about 80% by weight. Preferably 5% to 75% by weight and more specifically 10% to 65% by weight of the composition.
The lipophilic carrier may include fatty acid esters, fatty acids and vegetable oils, and mixtures thereof.
Fatty acid esters are a combination of fatty acid with a polyol, where the fatty acids are specifically medium chain fatty acids and the polyols include glycerol, propylene glycol, polyethylene glycol etc. The most commonly used medium chain fatty acid ester is medium chain triglycerides which are medium chain (C6 to C12) fatty acid such as include caproic acid, caprylic acid, capric acid and lauric acid esters with glycerol. They are commercially available under the brand names Labrafac™ lipophile WL 1349, Miglyol® 810, 812, 818 and 829, Crodamol™ GTCC, Captex® 350, 355 and 810D amongst many others.
Fatty acids include saturated or unsaturated fatty acids (C6 -C20) such as oleic acid, linoleic acid, caprylic acid or caproic acid.
The vegetable oils may be selected from wheat germ oil, soybean oil, olive oil, corn oil, palm oil, coconut oil, groundnut oil, sunflower oil, sesame oil, safflower oil, sweet almond oil and combinations thereof.
The concentration of the lipophilic vehicles present in the composition ranges from about 10% to about 90% wt. In an alternate embodiment of the invention, the concentration of lipophilic vehicle in the composition ranges particularly from about 20% to about 85 wt %.
The liquid pharmaceutical composition according to the invention may further comprises of hydrophilic vehicles, surfactants and emulsifying agents, antioxidants, chelating agents, sweeteners, flavors and preservatives.
The hydrophilic solvent used in the composition may include, but not limited to, monohydric alcohols, glycols, polyols and combinations thereof. Examples of hydrophilic carriers are ethanol, propylene glycol, polyethylene glycols, sorbitol and glycerin amongst others. The concentration ranges from 0.5% to 50% by weight and particularly 2% to 40% by weight of the composition.
The composition further may contain emulsifiers and surfactants, selected from, but not limited to the group consisting of fatty acids, mono and di glycerides, sorbitan fatty acid esters, polysorbate derivatives, polyoxyethylene sorbitan fatty acid esters, polyethoxylated castor oils, polyoxyethylene glycol glycerides, propylene glycol esters, fatty acid glycerol esters,Vitamin E TPGS, sodium lauryl sulphate, dioctyl sodium sulfosuccinate, poloxamers and mixtures thereof. Examples include but are not limited to oleic acid, glyceryl monostearate, sunflower seed glycerides, sunflower mono- diglycerides, caprylocapryolmacrogol glycerides, oleoyl polyoxyl-6 glycerides, lauroyl polyoxyl-32 glycerides, stearoyl polyoxylglycerides, D-a-tocopheryl polyethylene glycol succinatem, propylene glycol monocaprylate, span 60, polysorbate 80, poloxamer 188, polyoxyl 35 castor oil, and polyoxyl 40 castor oil.
Particularly emulsifiers and surfactants may be included in the compositions from 1.5% to about 60% by weight. More preferably the concentration of emulsifier and surfactant is between 2.5% to 50% by weight of the composition.
The pharmaceutical compositions of the present invention may include antioxidants such as butylated hydroxy toluene (BHT), butylated hydroxy anisole (BHA), ascorbyl palmitate, ascorbic acid, propyl gallate, tocopherol, sodium sulfite, sodium metabisulfite, sodium thiosulfate.
Chelating agents like disodium edetate, calcium disodium edetate, citric acid, tartaric acid may also be incorporated in the disclosed pharmaceutical compositions.

Suitable preservatives used in the compositions of the present invention include methyl paraben, ethyl paraben, propyl paraben, butyl paraben, sodium benzoate and combinations thereof.
Examples of sweeteners include sorbitol, mannitol, xylitol, saccharin, sodium or calcium saccharin, aspartame, acesulfame potassium, sodium cyclamate, sucraloseor a combination thereof.
Coloring agents and flavoring agents may be selected from any FDA approved colors and flavors for oral use.
The isotretinoin compositions disclosed in the present invention may further comprise of lipophilic and /or hydrophilic pharmaceutical excipients alone or in appropriate combination which are soluble or miscible with the phospholipid carrier phase and enhance the physical and or / chemical and or/ microbiological stability of the composition.
The compositions of the present inventions may be prepared using processes known to the person skilled in the field of pharmacy. According to one of the embodimentscomposition of the present invention is prepared by dissolving Isotretinoin in the lipophilic phospholipid carrier by continuous stirring at room temperature or higher temperature of about 45-50°C to minimize temperature associated degradation, although higher temperatures can also be used. Additionally, the composition is processed in a room where sodium vapor lamp is the source of light and an inert gas such as nitrogen is purged through the solution during manufacturing to protect the isotretinoin from oxidation due to atmospheric air or air entrapped in the carrier system.
According to another embodiment, the disclosed composition of Isotretinoin solution may be packed in suitable primary packaging made of glass or suitable plastics which provides an oxygen and light barrier and can store Isotretinoin solution throughout the shelf life. The packaging may be closedwith a suitable child resistant closures and the headspace in the bottle may be filled with an inert gas such as nitrogen. The liner material of closure coming in contact with the isotretinoin solution may be made of compatible materials such as expanded polyethylene, thin aluminum strip or any other non- reactive and non-shedding materials for maintaining stability of the composition.
According to another embodimentthe package may be supplied with a calibrated dosing device such as droppers, medication cup, dosing spoon, oral dosing syringe along with a neck adaptor for accurate measurement of the doses. The package also provides for flexible dosing of the pharmaceutical solution in addition to protecting the caregivers from exposure to the medication.
The composition of the present invention may be administered as such or after mixing with liquids such as water, milk, and /or soft foods such as ice cream, pudding, oat meal, butter, yogurt etc. prior to administration. Further, the composition is suitable for administration via the nasogastric tube in hospitalized patients unable to take the medication orally.
The present invention also relates to method of treatment of high risk neuroblastoma and severe recalcitrant nodular acne by administering an therapeutically effective dose of the composition of the present invention to a patient suffering from the disorder. Other diseases which require retinoid especially Isotretinoin treatment including but not limited to diseases such as seborrhea, recurrent glioblastoma multiforme (GBM), cervical cancers, advanced Kidney cancer, embryonal tumors of the central nervous system, T-cell malignancies, multiple myeloma, malignant glioma, relapsed or refractory solid tumors, acute myeloid leukemia, myelodysplastic syndrome, acute lymphocytic leukemia, head and neck cancer, acne vulgaris, pyoderma faciale, psoriasis, cutaneous lupus erythematosus, acne fulminans, generalizedlichen planus may also be treated by administering the disclosed invention of pharmaceutical solution comprising isotretinoin or pharmaceutically acceptable salts thereof, phospholipid carrier and optionally pharmaceutically acceptable excipients.
The present invention will be further explained by examples below. However, these examples are not intended to limit the scope of the present invention.
Examples
1.
S.No Composition %
1 Isotretinoin 5.7
2 Butylated hydroxyl Toluene 0.02
3 PHOSAL 53 MCT 94.28

2.
S.No Composition %
1 Isotretinoin 2.0
2 Butylated hydroxyl Toluene 0.02
3 PHOSAL50 PG 97.98

3.
S. No Composition %
1 Isotretinoin 2.0
2 Butylated hydroxyl Toluene 0.02
3. Polysorbate 80 10.0
3 PHOSAL 50SA+ 87.98

4.
S.No Composition %
1 Isotretinoin 5.3
2 Butylated hydroxyl Toluene* 0.02
3 Tween 80 6.6
4 PHOSAL 53 MCT 88.08
5.
S.No Composition %
1 Isotretinoin 4.0
2 Butylated hydroxyl Toluene* 0.03
3 Caprylocaproyl macrogol glycerides 30.0
4 PHOSAL 53 MCT 65.97

6.
S.No Composition %
1 Isotretinoin 4.0
2 Butylated hydroxyl Toluene* 0.03
3 Polysorbate 80 5.0
4 Caprylic and capric acid triglycerides 25.0
5 PHOSAL 53 MCT 65.98

7.
S.No Composition %
1 Isotretinoin 3.0
2 Butylated hydroxyl Toluene 0.03
3 Polyoxyl 35 castor oil 20.0
4 PEG 400 20.0
5 PHOSAL 53 MCT 56.97
8.
S.No Composition %
1 Isotretinoin 2.0
2 Butylated hydroxyl Toluene 0.03
3. Polyethylene glycol400 20.0
3. Polysorbate 80 10.0
3 PHOSAL 53 MCT 67.97
9.
S.No Composition %
1 Isotretinoin 4.0
2 Butylated hydroxyl Toluene* 0.03
3 Polysorbate 80 5.0
4 Soyabean oil 25.0
5 PHOSAL 53 MCT 65.98

The procedure needs to be carried out under sodium vapor lamp and continuous nitrogen purging. After dissolving the antioxidant in the Phosal carrier, Isotretinoin is dissolved in the system under continuous stirring. After the drug is completely dissolved and a clear solution is formed, rests of the ingredients are added.
Further the compositions can be filled into capsules as such or after adsorbing it on excipients such as silicon dioxide, lactose, microcrystalline cellulose, magnesium aluminosilicate etc.