Closure With Metered Dosing System

CLOSURE WITH METERED DOSING SYSTEM Field of the lnvention The present invention relates to a closure assembly comprising a metered dosing system which is installed upon a liquid drug formulation container to normally maintain the mouth of such a container closed during periods of non-use, but which, when opened, is operable to dispense the specified amount of said liquid drug formulation. Background of the Invention One of the critical aspects associated with the liquid drug formulations in the art is the accuracy of dose to be dispensed. Dispensing of accurate dose of liquid drug formulations has been achieved by using many pack designs. The general practice utilized in the art for dispensing of accurate dose involves the use of package system including measuring caps, measuring cups, droppers, measuring spoon with bottle, spoon associated with dropper, and spoon attached with cap. However, the packaging systems known in the art have been associated with certain short comings related to patient convenience, system design and operation. U.S. Patent No. 6,216,919 discloses a cap assembly having a measuring compartment, a slidable dispenser arm, a slidable dispenser spout, and an attachment device for coupling the cap assembly to a bottle. The cap assembly is designed to dispense the fixed amount of formulation. However, the structure of the whole assembly is complex in design and operation. Hence, there remains a need of a closure assembly comprising a metered dosing system for liquid dosage forms with simpler design and operation as compared to that disclosed in the art. The dosing system of the present invention has been designed to provide an in-built dosing mechanism which provides the benefit of ease in product dispensing. This concept eliminates the need of providing additional dosing components in the pack. The dosing system of the present invention is simple in design and operation and is of low cost with regard to both materials and labor. Summary of the lnvention An aspect of the present invention provides a closure assembly comprising a metered dosing system installed upon a liquid drug formulation container for dispensing of the said liquid drug formulation, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser. According to one of the embodiment of this aspect, there is provided a method of dispensing liquid drug formulation using a closure assembly comprising a metered dosing system installed upon a liquid drug formulation container, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser, and wherein the method comprises the steps of: unscrewing the cap, and dispensing the specified volume of liquid drug formulation pulled out into the doser. Brief description of the drawings Figure 1 (1A and 1 B) depicts components of the dosing system Figure 2 depicts the cap Figure 3 depicts the doser and it components Figure 3A depicts the first compartment of doser Figure 3B depicts the second compartment of doser Figure 4 depicts the metered dosing system and its functioning Detailed description of the lnvention The term "liquid drug formulation container" as used herein includes a container used to pack liquid drug formulation as described in the art of packaging of pharmaceutical liquid drug formulations the "liquid drug formulation container" preferably is a bottle. The liquid drug formulation may include, but not limited to syrups, elixirs, tinctures, mouth washes, gargles and the like. The "metered dosing system" as shown in figure 1A and figure 1 B comprises: > a cap 1 comprising a top wall and a perimeter side wall extending from the periphery of top wall, > a piston 2 fastened at the inner surface of the top wall of the cap, > a doser 3 attached to the cap and > a dip tube 4 attached to the doser. The cap 1 (Figure 1) is used to close the mouth of the container. The "cap" as shown in figure 2 comprises a top wall 1, a perimeter wall 2 extending from the periphery of top wall which may be threaded at inner surface. The threads at inner surface of perimeter wall functions to screw the cap with doser. The piston 2 (Figure 1) is fastened at the inner surface of top wall of the cap through a point of attachment leaving some space between inner surface of top wall of the cap and the piston. The position of piston is such that the piston is attached to the inner surface of top of the cap only through a point of attachment and the space is also present between periphery of the piston and perimeter wall of the cap. When the cap is screwed over the doser, the perimeter wall of doser fixes with the perimeter wall of cap through the space between the periphery of piston and perimeter wall of the cap. The space between piston and cap creates vacuum when the cap is screwed over the doser. The doser as shown in Figure 3 (Figure 3A and Figure 3B) is a hollow cylindrical assembly comprising cylindrical perimeter wall l',a partition wall 2'' originating from the inner surface of the cylindrical perimeter wall dividing the whole cylindrical space of the doser into two open compartments wherein the partition wall comprises an orifice 3'. The two compartments of doser having the partition wall in common and the perimeter wall originating from the periphery of partition wall defining the open space of two compartments. Figure 3A depicts the first open compartment and Figure 30 depicts the second open compartment. The two compartments have one common close end defined by two opposite surfaces of the partition wall and two opposite open ends. The first open compartment which comprises threads 4' at the outer surface of the perimeter wall is to be closed by the cap through the locking between threads present at the inner surface of perimeter wall of cap and outer surface of perimeter wall of first open compartment of doser. The second open compartment which comprises threads 4' on the inner surface of the perimeter wall is to be installed over the mouth of bottle through the locking between threads present on the inner surface of the perimeter wall of the second open compartment of doser and outer surface of the neck of bottle. The doser serves two purposes: (i) It acts as an attaching device of whole metered dosing system to the mouth of liquid drug formulation container. The first compartment of doser is attached to the cap comprising piston by screwing the cap over the perimeter wall. The second compartment of doser is attached to the mouth of the container. The second compartment is also attached to the dip tube through the orifice present at the partition wall. (ii) It functions to contain and dispense the liquid drug formulation pulled out of bottle when the cap is unscrewed. The doser, in its normal position is such that the first compartment of the doser having perimeter wall threaded outwardly is closed by the cap comprising piston, over the perimeter wall of the compartment. This compartment open end of that is closed by cap, which also acts to contain and dispense the liquid dosage sucked into it once the cap is unscrewed. The second open compartment of doser has perimeter wall threaded inwardly. The second open compartment also comprises one end of dip tube attached to the orifice present at the partition wall. This orifice extends through the thickness of the partition wall and connects both compartments of the doser. The second open compartment of the doser functions to mount the whole metered dosing system over the mouth of bottle through the thread locking between perimeter wall of the second open compartment and neck of the bottle. The dip tube 4 (Figure 1A and Figure 1B) is a simple tube as described in the art of packaging. One end of dip tube as shown in figure 3B is fastened with the tube extending from the periphery of orifice present at the partition wall of doser. Other end of dip tube is immersed in the liquid drug formulation present in the bottle. The dip tube helps in passing the liquid drug formulation from the bottle to the doser once suction is created by unscrewing the cap. The whole metered dosing system of the present invention in normal position is shown in figure 1B. The figure shows doser 3 covered by cap 1 comprising piston 2 screwed over the perimeter wall of first open compartment of doser and dip tube 4 in the second open compartment of the doser. The second open compartment can be installed over mouth of the liquid drug formulation container. The closure assembly comprising the metered dosing system installed upon a bottle and its functioning is shown in Figure 4. The dosing system functions on the basic principle of vacuum and suction of liquid due to vacuum. When the cap is screwed over the first compartment of doser, the vacuum is created between compartment of doser and cap comprising piston. When the cap is unscrewed the vacuum space creates the suction force that pulls the liquid drug formulation from the liquid drug formulation container to the doser's first compartment. The volume of pulled liquid is same as the volume of space between first compartment of doser and cap and piston in closed position. The metered dosing system of the present invention may also be provided with tamper evident feature. According to one of the embodiments of the present invention, there is provided a closure assembly comprising a metered dosing system installed upon a liquid drug formulation container for dispensing of the said liquid drug formulation, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser, and wherein the doser is a hollow cylindrical assembly comprising a cylindrical perimeter wall, a partition wall originating from the inner surface of the cylindrical perimeter wall dividing the whole cylindrical space of the doser into two open compartments, wherein the partition wall of the doser comprises an orifice. According to another embodiment of the present invention there is provided a closure assembly comprising a metered dosing system installed upon a liquid drug formulation container for dispensing of the said liquid drug formulation, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser, and whereinthe doser is a hollow cylindrical assembly comprising a cylindrical perimeter wall, a partition wall originating from the inner surface of the cylindrical perimeter wall dividing the whole cylindrical space of the doser into two open compartments, wherein the partition wall of the doser comprises an orifice, and wherein the perimeter wall of one open compartment of the doser is threaded at inner surface and the perimeter wall of the other open compartment of the doser is threaded at outer surface. According to yet another embodiment of the present invention, there is provided a closure assembly comprising a metered dosing system installed upon a liquid drug formulation container for dispensing of the said liquid drug formulation, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser, and wherein the doser is a hollow cylindrical assembly comprising a cylindrical perimeter wall, a partition wall originating from the inner surface of the cylindrical perimeter wall dividing the whole cylindrical space of the doser into two open compartments, wherein the partition wall of the doser comprises an orifice, and wherein the perimeter wall of one open compartment of the doser is threaded at outer surface, is closed by the cap and the perimeter wall of the other open compartment of the doser are threaded at inner surface installed over the mouth of bottle. Although, the preferred embodiments of the invention have been described in the specification, one skilled in the art will appreciate that various modifications and changes can be made in the closure assembly described for dispensing of liquid drug formulations without departing from the scope of the invention as is defined by the appended claims.

WE CLAIM: 1. A closure assembly comprising a metered dosing system installed upon a liquid drug formulation container for dispensing of the said liquid drug formulation, wherein the metered dosing system comprises a cap with a piston attached to the cap, a doser and a dip tube attached to the doser. 2. The closure assembly as claimed in claim I, wherein the liquid drug formulation container is a bottle. 3. The closure assembly as claimed in claim I, wherein the doser is a hollow cylindrical assembly comprising a cylindrical perimeter wall, a partition wall originating from the inner surface of the cylindrical perimeter wall dividing the whole cylindrical space of the doser into two open compartments. 4. The closure assembly as claimed in claim 3, wherein the partition wall of the doser comprises an orifice. 5. The closure assembly as claimed in claim 3, wherein the perimeter wall of one open compartment of the doser is threaded at outer surface. 6. The closure assembly as claimed in claim 3, wherein the perimeter wall of the doser threaded at outer surface is closed by the cap. 7. The closure assembly as claimed in claim 3, wherein the perimeter wall of one open compartment of the doser is threaded at inner surface. 8. The closure assembly as claimed in claim 3, wherein the perimeter wall the doser threaded at inner surface is installed over the mouth of bottle. 9. A method of dispensing of liquid drug formulation using the closure assembly as claimed in claim I, wherein the method comprises i. unscrewing the cap, and ii. dispensing a volume of the liquid drug formulation pulled out into the doser. 10.A closure assembly comprising metered dosing system as described and illustrated in the figures herein. Dated this the 26TH day of July, 2013. For Ranbaxy Laboratories Limited 1Dr. Santanu De) Associate Director and Head IP India