DESC:FIELD OF THE INVENTION:
The present invention relates to oral liquid formulation of lapatinib in a suspension dosage form. Further, the present invention relates to providing a novel, economical and technically advanced dosage form over existing dosage form.

BACKGROUND OF THE INVENTION:
Lapatinib is a small molecule of dual tyrosine kinase inhibitor which interrupts the HER2/neu and epidermal growth factor receptor (EGFR) pathways. It is orally active drug used for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress HER2 (ErbB2).

It is present as the monohydrate of the ditosylate salt, with chemical name N-{3-chloro-4-[(3-fluorophenyl) methoxy]phenyl}-6-(5-{[(2-ethanesulfonylethyl) amino] methyl}furan-2-yl)quinazolin-4-amine and molecular formula C29H26ClFN4O4S (C7H8O3S)2 H2O and a molecular weight of 943.5.

Structurally, lapatinib ditosylate monohydrate is represented as below:

LAPATINIB

Lapatinib is disclosed in US patent no. WO1999035146 and is marketed under the brand name of Tykerb® (by Glaxo Smith Kline) which is of 250mg, orange colored, oval shaped -biconvex, film-coated tablet for oral administration. Each 250mg tablet of Tykerb® contains lapatinib ditosylate monohydrate or 250mg lapatinib free base along with the inactive ingredient’s magnesium stearate, microcrystalline cellulose, povidone, sodium starch glycolate and for coating of orange film-coat, FD&C yellow no. 6/sunset yellow FCF aluminum lake, hypromellose, macrogol/PEG 400, polysorbate 80 and titanium dioxide.

The recommended dosage of Tykerb® for advanced or metastatic breast cancer is 1250mg (5 tablets) given orally once daily on days 1-21 continuously in combination with capecitabine 2000mg/m2/day (administered orally in 2 doses approximately 12 hours apart) on days 1-14 in a repeating 21-day cycle.

Breast cancer is one of the most common form of cancer in women worldwide. As per WHO, breast cancer caused 670000 deaths globally in 2022. Breast cancer was the most common cancer in women in 157 countries out of 185 in 2022.

Although treatment with chemotherapy, endocrine therapy and targeted therapy has significantly improved the outcomes for women with early-stage disease, overall survival for women with metastatic disease remains poor with a five-year survival rate of only 15% underscoring the need for novel therapeutic strategies.

PCT publication no. WO2010023187 discloses a pharmaceutical composition with a high percentage of lapatinib as active pharmaceutical ingredient present in an amount of more than 60% by weight based on the total weight of the composition. The term pharmaceutical composition in WO2010023187 is referred to single solid dosage forms, such as tablets, capsules, pellets, etc., as well as powders or granules which are used in the preparation of single dosage forms. The preferred pharmaceutical composition is in the form of tablets.

PCT publication no. WO2010023188 discloses pharmaceutical compositions comprising lapatinib or a pharmaceutically acceptable salt thereof wherein a unit dose of the composition contains 1200 to 1300mg of the active pharmaceutical ingredient calculated as the free base. The pharmaceutical composition is in form of an effervescent tablet, syrup, granulates suitable for suspension and pellets. The pellets and granulate are intended for the preparation of a suspension by adding a suitable liquid, e.g. water. No stability studies have provided.

Koch et al (first published on 07 July 2014) discloses relative bioavailability study indicating that administration of Lapatinib 1250mg as tablets dispersed in water (oral suspension) prior to ingestion was bioequivalent (BE) to tablets that were swallowed intact. The suspension was prepared and administered immediately to overcome the hydrolysis potential of Lapatinib in a water-based formulation. The study has admitted that although dispersing the tablets in water is clearly an option, a true oral suspension is preferred.

Existing dosage form comprises lapatinib in tablet oral form. Tablets are not suitable for old age patients because they cannot take it easily and some drugs cause gastric irritation when they are given in the tablet form. Moreover, cancer patients are usually on a numerous drug regimen demanding the administration of large numbers of tablets or capsules often along with intravenous therapy. Patient compliance in such a regimen can be addressed by decreasing the number of tablets or capsules administered as well as the type of dosage forms that are administered, considering the bioavailability of the administered drug. The drug bioavailability cannot be compromised to meet patient compliance.

Oral liquid dosage forms are the most suitable dosage form for patients who have difficulty taking tablets or capsules, as might be the case with pediatric or geriatric patients. They are attractive in appearance and give beneficial psychological effects. The present invention relates to the Lapatinib in a liquid oral suspension dosage form that does not use sophisticated techniques and is economically affordable compared to available dosage form. Further, the formulated oral liquid suspension dosage form prepared as per the present invention provides greater stability.

Lapatinib is known to elicit undesirable bitter or bad taste. Hence, patient compliance is a factor that may impede administration and prevent effective treatment. The present invention further provides oral suspension comprising taste-masking agents that enables ease in administration leading to greater patient compliance.

A suspension is a heterogeneous mixture that contains solid particles sufficiently large for sedimentation. The suspended particles do not dissolve and remain suspended throughout the bulk of the liquid medium. The suspended particles may be visible to the naked eye which is usually larger than 1 micrometer. Generally, the solid part is dispersed through mechanical agitation using suspending agents. In contrast, solution have dissolved and homogeneously mixed solute which does not exist as a solid. Lapatinib suspension is highly viscous and particles adheres to bottle. Hence, there is a need to provide Lapatinib suspension wherein Lapatinib particles remain suspended, does not stick and reconstitutes easily when shaken.

The present invention incorporates smaller particle size of suspension that increases the solubility of lapatinib and thus providing better dissolution profile. The solubility and stability of the patient compliant lapatinib formulation, prepared as per the present invention, is proven higher when compared to prior art inventions.

Further, the present invention provides a suspension composition prepared by a process which is relatively simple, easy to commercially manufacture, and functionally reproducible. Additionally, a suspension composition of the present invention is also able to incorporate two or more active ingredients.

OBJECTIVE OF THE INVENTION:
The prime objective of the present invention is to provide an oral liquid composition of lapatinib preferably as suspension dosage form with pharmaceutically acceptable excipients and method of preparation thereof.

In another objective, a pharmaceutical composition as per the present invention comprises lapatinib or pharmaceutically acceptable salt thereof.

In yet another objective of the present invention, the pharmaceutical composition manufactured has particle size ranging from nanometer to micrometer, which results in enhanced in-vitro dissolution profile, of about 80% to 110% enhanced dissolution profile. The D90 of particle size is in the range of 2 to 50 microns.

In yet another objective of the present invention, the pharmaceutical composition is manufactured by homogenization and mixing.

Additional objective according to the present invention relates to a stable suspension.

One objective of the present invention may includes a pharmaceutical composition comprising about 5% to 50% w/v of lapatinib with pharmaceutically acceptable excipients.

In another objective of the present invention, wherein the solubilizers and cosolvent present in the pharmaceutical composition enhances absorption of lapatinib owing to their optimum hydrophilic and hydrophobic properties.

In yet another objective of the present invention the composition of Lapatinib comprising solubility enhancer and permeability enhancer, which are not the part of the current dosage form available in market.

In yet another objective of the present invention the pharmaceutical composition may include lapatinib as an active ingredient with one or more selected from pharmaceutically acceptable excipients like diluent vehicles, stabilizers / anti-oxidants, suspending / thickening agents, chelating / complexing agents, solubility enhancing agents, permeability enhancers, preservatives, glidants, active carriers, sweeteners, anti-caking agents, wetting agents, preservatives, buffering agents, flavoring agents and the like.

In yet another objective of the present invention relates to process for preparation of an oral pharmaceutical composition as per the present invention comprising following steps:
a) Adding diluent vehicle in purified water;
b) adding cosolvent and homogenization;
c) adding solubilizer and homogenization;
d) adding lapatinib and homogenization to get homogeneous suspension;
e) adding sweetening agent in above-prepared suspension and mixing the same through vortex or high-speed homogenizer or mechanical or sonicated or shear stress to obtain a uniform suspended formulated dosage form;
f) dissolving suspending agent and thickening agent in above prepared suspension to provide appropriate viscosity;
g) dissolving flavouring agent;
h) making-up volume of the above suspension with aqueous vehicle.

In yet another objective, the present invention elicits favourable pharmacokinetic profile.

SUMMARY OF THE INVENTION:
One aspect of the present invention relates to an oral composition of lapatinib preferably as liquid suspension dosage form with pharmaceutically acceptable excipients and method of preparation thereof.

One aspect of the present invention relates to the pharmaceutical composition manufactured as a suspension.

One aspect of the present invention relates to the pharmaceutical composition comprising lapatinib as an active ingredient with one or more selected from pharmaceutically acceptable excipients like diluent vehicles, stabilizers / anti-oxidants, suspending / thickening agents, chelating / complexing agents, solubility enhancing agents, permeability enhancers, preservatives, glidants, active carriers, sweeteners, anti-caking agents, wetting agents, preservatives, buffering agents, flavoring agents and the like.

One aspect of the present invention relates to process for preparation of an oral pharmaceutical composition as per the present invention comprising following steps:
a) adding diluent vehicle in purified water;
b) adding cosolvent and homogenization;
c) adding solubilizer and homogenization;
d) adding lapatinib and homogenization to get homogeneous suspension;
e) adding sweetening agent in above-prepared suspension and mixing the same through vortex or high-speed homogenizer or mechanical or sonicated or shear stress to obtain a uniform suspended formulated dosage form;
f) dissolving suspending agent and thickening agent in above prepared suspension to provide appropriate viscosity;
g) dissolving flavouring agent;
h) making-up volume of the above suspension with aqueous vehicle.

DETAILED DESCRIPTION OF THE INVENTION:
The present invention will now be disclosed by describing certain preferred and optional embodiments, to facilitate various aspects thereof.

In accordance with the present invention, a pharmaceutical composition comprising lapatinib as an active ingredient with pharmaceutically acceptable excipients.

The term "pharmaceutically acceptable excipients" as used herein, refers to excipients used in pharmaceutical compositions. The pharmaceutically acceptable excipients may comprise of diluent vehicles, stabilizers / anti-oxidants, suspending / thickening agents, chelating / complexing agents, solubility enhancing agents, preservatives, glidants, sweeteners, anti-caking agents, wetting agents, preservatives, buffering agents, flavoring agents and combinations thereof.

Suitable diluent vehicle may include one or more selected from aqueous vehicle, water, sugar, methylcellulose gel, citric acid, sucrose, sorbitol solution, sodium carboxy methylcellulose solution, xanthan gum solution, non-aqueous vehicle like refined fractionated coconut oil, hydrogenated castor oil, lecithin, aluminum stearate and the like.

Suitable suspending or thickening agents may include one or more selected from sodium alginate, methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, povidone K120, colloidal silicon dioxide, carboxymethyl cellulose, sodium carboxymethyl cellulose, acacia, tragacanth, xanthan gum, carbomer, carrageen, gelatin and the like. Lapatinib suspension was stable and remained suspended. At different time intervals, content uniformity showed uniform distribution of lapatinib ditosylate monohydrate in suspension and decreased sedimentation. Sedimentation does not affect the stability of Lapatinib. Lapatinib was easily resuspended into a homogeneous liquid after gentle shaking of the suspension.

Suitable co-solvent may include one or more selected from ethanol, propylene glycol, glycerine, glycofural, polyethylene glycols and the like.

Suitable preservative may include one or more selected from propylene glycol, disodium EDTA, benzalkonium chloride, benzoic acid, butyl paraben, methyl paraben, propyl paraben, sodium benzoate and the like.

Suitable sweetener may include but are not limited to one or more selected from sucralose, sachharin, neotame, asparmate, cyclamte, glycyrrhizin, sucrose, molases, glucose, fructose, mannitol, sorbitol, xylitol, erythritol, Isomalt, maltiol, lactiol, hydrogenated starch and the like.

Suitable flavoring agents may include one or more selected from the group consisting of peppermint, grapefruit, orange, lime, lemon, mandarin, pineapple, strawberry, raspberry, mango, passion fruit, kiwi, apple, pear, peach, apricot, cherry, grape, banana, cranberry, blueberry, black currant, red currant, gooseberry, lingon berries, cumin, thyme, basil, camille, valerian, fennel, parsley, tarragon, lavender, dill, bargamot, salvia, aloe vera balsam, spearmint, piperine, eucalyptus, and the like.

The solubility enhancing agent is a substance added to a formulation to increase the solubility of a poorly soluble drug, allowing more of the active ingredient to dissolve in the liquid medium, thereby improving the drug's bioavailability and absorption when administered as a suspension. Suitable solubility enhancing agents may be selected from water and one or more from the group comprising surfactants such as (1) non-ionic e.g., polyoxyethylene sorbitan fatty acid esters, sorbitan esters, Tween 80, polyoxyethylene ethers, (2) anionic e.g., sodium lauryl sulfate, sodium laurate, dialkyl sodium sulfosuccinates, particularly bis-(2-ethylhexyl) sodium sulfosuccinate, and sodium oleate (3) cationic e.g., benzalkonium chloride, cetylpyridinium chloride and benzethonium chloride, and (4) zwitterionic / amphoteric surfactants; fatty alcohols such as lauryl, cetyl, and stearyl alcohols; glyceryl esters such as the naturally occurring mono-, di-, and tri-glycerides; fatty acid esters of fatty alcohols and other alcohols such as propylene glycol, polyethylene glycol; sucrose; polymers e.g., poloxamers, polyvinylpyrrolidones, glycerides e.g., triacetin, glyceryl monocaprylate, diethylene glycol monoethyl ether; polyethylene glycols and the like.

In one embodiment of the present invention, the D90 of the active ingredient in the pharmaceutical composition is in the range of 2µ to 50µ. Example 8 discloses the impact of different particle size on dissolution. Excellent dissolution is obtained for D90 between 14µ to 41µ.

In yet another embodiment of the present invention, the pharmaceutical composition results in enhanced in-vitro dissolution profile of about 80% to 110%. Example 9 relates to dissolution Tykerb® (Lapatinib tablet 250mg) v/s Lapatinib suspension 500mg/5mL. Lapatinib suspension of the present invention provides excellent dissolution as compared to Lapatinib tablet 250mg.

Additional embodiment according to the present invention is a stabilized suspension. The pharmaceutical dosage form prepared as per the present invention is stable for 6months at 2-8°C and at 25°C ± 2°C/60% ±5%RH as per Example 11.

In yet another embodiment of the present invention, the pharmaceutical composition manufactured is suspension, which results in enhanced in-vitro dissolution profile as per Example 9.

In another embodiment, a pharmaceutical composition as per the present invention comprises Lapatinib or pharmaceutically acceptable salt thereof.

In yet another embodiment of the present invention, wherein the pH of the pharmaceutical composition is in the range of 3.5 - 7.

In yet another objective, the present invention elicits favorable pharmacokinetic profile.

In yet another objective, on visual inspection no noticeable change in the viscosity of the present invention was seen. Highly viscous suspension makes withdrawing doses from the bottle challenging but also prevents homogeneous distribution of the suspensions even after shaking.

Another embodiment of the present invention is the liquid formulation administered orally once a day or more.

In one embodiment, process for preparation of an oral pharmaceutical composition as per the present invention comprising following steps:
a) adding diluent vehicle in purified water;
b) adding cosolvent and homogenization;
c) adding solubilizer and homogenization;
d) adding lapatinib and homogenization to get homogeneous suspension;
e) adding sweetening agent in above-prepared suspension and mixing the same through vortex or high-speed homogenizer or mechanical or sonicated or shear stress to obtain a uniform suspended formulated dosage form;
f) dissolving suspending agent and thickening agent in above prepared suspension to provide appropriate viscosity;
g) dissolving flavouring agent;
h) making-up volume of the above suspension with aqueous vehicle.

The invention will be further described with respect to the following example However; the scope of the invention is not limited thereby. All percentages stated in this specification are by weight, unless otherwise specified. While the present 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 present invention.

EXAMPLE 1:
Lapatinib 50mg/ml (250mg/5ml) Oral Suspension
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 405 8.10
2. Sorbitol solution 70% 1484.00 29.68
3. Tween 80 28.57 0.57
4. Sucralose 2.00 0.04
5. Xanthan gum 2.50 0.05
6. strawberry flavour 4.00 0.08
7. Purified water Q.S to make 5 mL q.s.
Total weight 5000.00 100.00

EXAMPLE 2:
Lapatinib 50mg/ml (250mg/5ml) Oral Suspension
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 1250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 2025 40.50
2. Sorbitol solution 70% 1484.00 29.68
3. Tween 80 28.57 0.57
4. Sucralose 2.00 0.04
5. Xanthan gum 2.50 0.05
6. strawberry flavour 4.00 0.08
7. Purified water Q.S to make 5 mL q.s.
Total weight 5000.00 100.00

EXAMPLE 3:
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 405.00 8.10
2. Sorbitol solution 70% 1441.50 28.83
3. Tween 80 25.00 0.50
4. Polyethylene glycol 400 100.00 2.00
5. Sucralose 2.00 0.04
6. Xanthan gum 2.50 0.05
7. strawberry flavour 4.00 0.08
8. Purified water Q.S to make 5 mL q.s.
Total weight 5000.00 100.00

EXAMPLE 4:
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 1250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 2025 40.50
2. Sorbitol solution 70% 1441.50 28.83
3. Tween 80 25.00 0.50
4. Polyethylene glycol 400 100.00 2.00
5. Sucralose 2.00 0.04
6. Xanthan gum 2.50 0.05
7. strawberry flavor 4.00 0.08
8. Purified water Q.S to make 5 mL q.s.
Total weight 5000.00 100.00

EXAMPLE 5:
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 405.00 8.10
2. Sorbitol solution 70% 1441.50 28.83
3. Polyethylene glycol 400 25.00 0.50
4. Sodium lauryl sulfate 50.00 1.00
5. Citric acid 10.00 0.20
6. Methyl paraben 4.00 0.08
7. Propyl paraben 1.00 0.02
8. Sucralose 2.00 0.04
9. Xanthan gum 2.50 0.05
10. strawberry flavor 4.00 0.08
11. Purified water Q.S to make 5 mL
(2460.00 mg) 49.20
Total weight 5000.00 100.00

EXAMPLE 6:
Sr. No Ingredient(s) Qty./dose(mg)
Strength: 1250 mg/5 ml % w/w
1. Lapatinib ditosylate monohydrate 2025 40.50
2. Sorbitol solution 70% 1441.50 28.83
3. Polyethylene glycol 400 25.00 0.50
4. Sodium lauryl sulfate 50.00 1.00
5. Citric acid 10.00 0.20
6. Methyl paraben 4.00 0.08
7. Propyl paraben 1.00 0.02
8. Sucralose 2.00 0.04
9. Xanthan gum 2.50 0.05
10. Strawberry flavor 4.00 0.08
11. Purified water Q.S to make 5 mL
(2460.00 mg) 49.20
Total weight 5000.00 100.00

EXAMPLE 7:
Sr. no Ingredients Function Qty/dose
Strength: 500 mg/ 5ml % w/w
1. Lapatinib ditosylate monohydrate API 810.00 16.2
2. Sorbitol 70 % Diluent 2078.50 41.57
3. Tween 80 Solubilizer 50.00 1.00
4. Polyethylene glycol 400 Cosolvent 1650.00 33.00
5. Methyl paraben Preservative 4.00 0.08
6. Propyl paraben Preservative 1.00 0.02
7. Sucralose Sweetening agent 2.00 0.04
8. Xanthan gum Suspending agent 0.50 0.01
9. Strawberry flavour Flavouring agent 4.00 0.08
10. Purified water Vehicle Qty to make 5 ml (400 mg) Q.s.
Total weight 5000.00 100.00

EXAMPLE 8:
Effect of different Particle size of Lapatinib ditosylate monohydrate on dissolution.
Time (Min) Low
Particle size Optimum
Particle size High
Particle size
Particle size(µ) D90: 14µ D90: 27µ D90: 41µ
Condition: 2% Polysorbate 80 in 0.1 N HCl, 900 mL, Paddle, 55 RPM
10 64.8 60.9 56.7
15 75.6 71.5 66.2
20 87.8 89.1 87.3
30 94.5 94.9 98.7
45 98.5 99.4 100.9

EXAMPLE 9:
Dissolution data of Tyverb (Lapatinib tablet 250mg) v/s Lapatinib suspension 500mg/5mL.
Time (Min) Tyverb (Lapatinib tablet 250mg) Lapatinib suspension 500mg/mL (Example 7)
Condition: 2% Polysorbate 80 in 0.1 N HCl, 900 mL, Paddle, 55 RPM
10 43.4 60.9
15 70.5 71.5
20 80.7 89.1
30 87.5 94.9
45 90.9 99.4

EXAMPLE 10:
Effect of concentration of solubility enhancer on the dissolution of Lapatinib ditosylate.
Time (Min) Low Concentration of Solubility enhancer
(0.5%) Optimum Concentration of Solubility enhancer
(1.0%) High Concentration of Solubility enhancer
(1.5%)
Condition: 2% Polysorbate 80 in 0.1 N HCl, 900 mL, Paddle, 55 RPM
10 51.6 60.9 67.5
15 62.9 71.5 78.2
20 87.6 89.1 90.6
30 96.5 94.9 98.0
45 99.3 99.4 102.0

EXAMPLE 11:
Stability Study summary of Lapatinib ditosylate suspension 500mg/5ml
The pharmaceutical dosage form prepared as per the present invention was found to be adequately stable for 6months at 2-8°C and at 25°C ± 2°C/60% ±5%RH.
Sr.
No Description Specification Initial 6 Months 6months
1. Storage conditions - 2-8°C ± 5°C
And
25°C ± 2°C/ 60% ±5%RH 2-8°C ± 5°C 25°C ± 2°C/ 60% ±5%RH
2. Description Yellowish colored Suspension Complies Complies Complies
3. Assay % NLT 90.0 % to NMT 110.0% of label claim 99.7% 99.2% 101.7%
4. Dissolution NLT 75.0 % (Q) of label amount in 30 min 94.9% 96.7% 95.9%
5. Related Substance
Impurity-A NMT 0.2 % 0.02% 0.02% 0.02%
impurity-B NMT 0.2 % Not Detected Not Detected Not Detected
impurity-C NMT 0.2 % Not Detected Not Detected Not Detected
Dimer Impurity NMT 0.2 % 0.01% 0.01% 0.01%
Any unknown impurity NMT 2.0 % 0.10% 0.10% 0.18%
Total Impurities NMT 1.5 % 0.28% 0.27% 0.46%
6. Microbial Limit Test
Total Aerobic bacterial count NMT 102cfu/ml Less than 100 cfu/ml Less than 100 cfu/ml Less than 100 cfu/ml
Total Combined Yeasts and Moulds Count NMT 10cfu/ml Less than 10 cfu/mI Less than 10 cfu/mI Less than 10 cfu/mI
E. Coli Should be absent per ml Absent/ml Absent/ml Absent/ml

The invention described herein comprises in various objects as mentioned above and their description in relation to characteristics, compositions and process adopted. While these aspects are emphasised in the invention, any variations of the invention described above are not to be regarded as departure from the spirit and scope of the invention as described
,CLAIMS:1. A novel pharmaceutical composition of Lapatinib oral suspension comprising of Lapatinib or pharmaceutically acceptable salt thereof and at least one or more pharmaceutically acceptable excipients.

2. The oral pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1 comprising
a) Lapatinib in the range of 5%w/w to 50%w/w.
b) One or more diluent in the range of 0.2% w/w to 45%w/w.
c) One or more co-solvent in range of 0.50% w/w to 40% w/w.
d) One or more co-solubilizer in range of 0.30% w/w to 1.5% w/w.
e) One or more suspending agent in range of 0.01% w/w to 1.0% w/w.
f) One or more of sweetening and flavouring agents in the concentration not more than 0.5 % w/v.
g) optionally one of more pH adjusting agents in the concentration not more than 0.02% w/w.

3. The pharmaceutical composition as claimed in claim 1 Lapatinib monohydrate ditosylate comprises D90 in the range of 2 to 50 microns.

4. The novel pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1, wherein the diluent is selected one or more from aqueous vehicle, water, sugar, methylcellulose gel, citric acid, sucrose, sorbitol solution, sodium carboxy methylcellulose solution, xanthan gum solution, non-aqueous vehicle like refined fractionated coconut oil, hydrogenated castor oil, lecithin, aluminum stearate and the like.

5. The novel pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1, wherein the cosolvent is selected one or more from ethanol, propylene glycol, glycerine, glycofural, polyethylene glycols and the like.

6. The novel pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1, wherein the solubilizer is selected one or more from Tween 80, sodium lauryl sulfate, sodium stearate, potassium stearate, sodium oleate and the like.

7. The novel pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1, wherein one or more suspending agent is selected from sodium alginate, methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, povidone K120, colloidal silicon dioxide, carboxymethyl cellulose, sodium carboxymethyl cellulose, acacia, tragacanth, xanthan gum, carbomer, carrageen, gelatin and the like.

8. The novel pharmaceutical composition of Lapatinib oral suspension as claimed in claim 1, wherein one or more sweetening and flavouring agent is selected from sucralose, sachharin, neotame, strawberry, raspberry, mango and like.

9. The novel pharmaceutical composition of Lapatinib oral suspension comprising of following formula:
Ingredients % w/w
Lapatinib ditosylate monohydrate 16.2
Sorbitol 70 % 41.57
Tween 80 1.00
Polyethylene glycol 400 33.00
Methyl paraben 0.08
Propyl paraben 0.02
Sucralose 0.04
Xanthan gum 0.01
Strawberry flavour 0.08
Purified water Q.s.

10. The process of preparing oral pharmaceutical composition as claimed in claim 1 comprising:
a) adding diluent vehicle in purified water;
b) adding cosolvent and homogenization;
c) adding solubilizer and homogenization;
d) adding lapatinib and homogenization to obtain homogeneous suspension;
e) adding sweetening agent in above-prepared suspension and mixing the same through vortex or high-speed homogenizer or mechanical or sonicated or shear stress to obtain a uniform suspended formulated dosage form;
f) dissolving suspending agent and thickening agent in above prepared suspension to provide appropriate viscosity;
g) dissolving flavouring agent;
h) making-up volume of the above suspension with aqueous vehicle.