MXPA01002620A - Needleless injector cartridge - Google Patents

Abstract

A needleless injector cartridge, comprises an injection component (1) defining a void (17) therein for receiving medicament, and having an injection discharge orifice communicating with the void. The cartridge further comprises a transfer device (2) comprising a liquid-containing reservoir (4), and transfer means for causing the liquid (5) to flow from the reservoir, through a reservoir outlet, into the void in the injection component.

Description

INJECTOR CARTRIDGE WITHOUT NEEDLE DESCRIPTION OF THE INVENTION This invention relates to needle-free injection cartridges. Needleless injectors are used as an alternative to conventional hypodermic needles to inject liquid medications into a patient's tissues. The usual principle of operation is a high pressure piston pump, which drives a jet of liquid with sufficient force to penetrate the epidermis and deposit in the underlying tissues. Such devices have been available for more than fifty years and most examples are multi-dose devices, i.e., a succession of doses can be expelled from a reservoir, each dose being dispensed from an integral pressure chamber. The motive power can be derived from electrical, manual, pyrotechnic or pressurized gas, stored. In the 1980s, some reports of cross contamination were presented by using multiple dose injectors, which promoted a search for safer forms, and then a plurality of injectors was invented, comprising a multi-dose power unit or actuator. , to which a disposable injection cartridge could be attached. These cartridges were usually intended to be filled by the user with the help of a transfer device, through which a medication could be extracted from a bottle and transferred to a cartridge. This is a number of problems that arise from this aspect: it is practically impossible to obtain an aseptic transfer of the medication; there is a likelihood that there will be significant amounts of air bubbles trapped in the cartridge, which reduces the operation of the injection; and there is the opportunity to prepare an incorrect amount that will be injected. Few attempts were made to supply pre-filled cartridges, but most of the proposed materials for cartridges were not suitable for long-term contact with the drug, or at least they required extensive and very expensive validation for each application. Boron silicate glass is the ideal material for most applications, since it has the required inertia, transparency, and barrier properties. However, the pressures achieved in needleless injectors can be very high, of the order of 600 bars, and a cartridge made of glass requires a very careful design and processing to avoid rupture. The co-pending application published under No. WO 98/13086 describes a method for manufacturing glass injection cartridges, but the process requires a large investment in the specialist plant in order to obtain the low cost component necessary for many applications . Some drugs can not be stored for long periods in glass however, and, therefore, have to be stored in some other material. In such cases, that other material is unlikely to continue resisting high injection pressures. The present invention seeks to overcome the disadvantages of the prior art devices by providing a needleless injector cartridge, which includes a reservoir of liquid medicament as a bonded part thereof, with means for transferring the liquid from the reservoir into the cartridge part from which the injection is presented. According to the invention, there is provided a needleless injector cartridge comprising: an injection component defining a gap therein for receiving the medicament, and having an injection discharge orifice with the recess; and a transfer device comprising a reservoir containing liquid, and transfer means for causing the liquid to flow from the reservoir, through a reservoir outlet, into said recess. Preferably, the reservoir is made of glass, but other materials may be used if the virio is unsuitable for a long-term storage contact with the medicament. The injection component may be of a material suitable for short-term contact with the medicament, and suitable for extremely high injection pressures. Stainless steel or liquid crystal polymer are two different materials, which may be suitable, or a combination of materials may be used to To optimize the requirements of cost, operation and size, for example, an inexpensive polypropylene cartridge can be housed in a steel cover, the latter providing support for the plastic during the injection. In a first preferred embodiment, a plastic injection component is provided, which preferably is a cylinder containing a piston, and having a small discharge orifice at one end. Attached, preferably coaxially, to the injection component at the discharge end, there is an open cylinder in which a reservoir made of a material compatible with the medicament contained therein is placed. The reservoir has a discharge tube that is sharpened at one end, and at the other end contains a plunger, with the medicament contained between the plunger and the discharge tube. An elastomeric seal surrounds and seals on the outside of the discharge tube and also seals against the discharge orifice of the injection component. The seal provides a conduit between the reservoir and the injection component, but is temporarily blocked by a septum. The piston in the injection component is located in order to allow the latter to receive the required volume of liquid, and the gap between the piston and the septum is evacuated. A screw cap on the reservoir holder acts on the plunger in the reservoir, so that when the cap is rotated the plunger drives the reservoir forward until the reservoir discharge tube pierces the septum. The continuous movement of the lid sucks the volume required medication from the deposit to the injection component. The reservoir support, reservoir, plunger and cap are then separated together and the filled injection component is ready for use. The use of the screw cap allows the user to move the plunger firmly, in a manner that avoids any sudden jolt, thus reducing the possibility of the liquid experiencing undesirable foaming. It also means that a larger force can be exerted on the plunger, thus allowing the use of a plunger of larger diameter than would otherwise be the case. This in turn means that the reservoir can be shorter, thus helping to keep the entire length of the transfer device short. The cartridge can be attached to a multipurpose actuator or a device for individual use, or have been pre-assembled prior to filling. A second preferred embodiment provides a device for transferring a liquid as described in the first preferred embodiment, wherein a lyophilized drug (freeze drying) or other dry material is maintained within the evacuated injection component, and the liquid transfer in the described way dissolves the material so that it can be injected. A third preferred embodiment is similar to the first, except that the reservoir is equipped with two pistons, separate, and containing the liquid within the space. The forward movement of the plungers causes the liquid to reach one or more Bypass slots in the tank wall, so that the liquid passes through the slots and into the injection component. In all the embodiments described above, there is a gap within the cartridge, so that the likelihood of a large gas bubble becoming trapped when the liquid is transferred is reduced. The piston inside the injection component is held in place with sufficient friction to prevent its movement due to the pressure differential. If the existence of bubbles is not particularly important, then a fourth embodiment presents the piston placed initially near the injection discharge orifice of the injection component, and when the content of the reservoir is transferred, the piston moves in response to the hydraulic pressure. created by the transfer mechanism. This method does not require the evacuation of the drug chamber before filling, but if it is necessary to reduce the trapped air in a very small volume, evacuation of the hollow inside the capsule before filling will achieve this objective. The invention is described in more detail with reference to the accompanying drawings, all of which are central line sections of substantially cylindrical devices. Figure 1 shows the separable deposit; Figure 2 shows a reservoir and injection component assembly suitable for hydraulic displacement of the piston; Figure 3 shows the device with a lyophilized drug pellet; Figure 4 shows a tank and injection component assembly; Figure 5 shows a similar assembly with a separate liner within the injection component body; Figure 6 shows a cartridge after transferring the medication from the reservoir; Figure 7 shows the separate reservoir components of the injection component; Figures 8 and 9 show a deviation mode of the invention. For clarity, similar parties are given a similar annotation when possible. Referring to Figure 1, the injection component 1 for needleless injection has a reservoir holder 2 attached through a brittle connection 3. Slidably located within the holder 2 is the medicament reservoir 4 containing a liquid medicament 5. A discharge tube 6 is attached to, or integral with , reservoir 4 in fluid connection with the medication , and ends with a sharp bevel 7. A tubular seal 8 protects against the entry of bacteria both towards the medicament 5 and to the discharge orifice 9 of the injection component 1. A plunger 10 is sealed and slidably assembled in the reservoir hole 4 and in contact with the medicament 5: preferably there is not (or only a small amount of) air entrapped within the medicament 5. A screw cap 11 is assembled to the reservoir support 2, and it has a central bar, which engages with the plunger 10. The seal 8 has a septum 13, which, until punctured, prevents the contents of the reservoir 4 from being transferred to the injection component 1. With reference to Figure 4 , the injection component 1 has a piston 14 sealed and slidably assembled therein, and has a thread 15 for attachment to a needleless injector actuator or power unit. Alternatively, the attachment means may be a snap fastener, a separate fastener, or other convenient means to facilitate the current design of the device and application, or the cartridge may be integral with the power unit. Figure 5 is similar to Figure 4, except that the injection component 1 comprises a separate liner 16 fitted therein, in order to provide specific properties to the drug and application. In both Figure 4 and Figure 5, the gap 17 between the piston 14 and the septum 13 is evacuated, ie 0.1 bar. Figure 6 shows the screw cap 11 operated so that the bar 12 pushes the plunger 10 towards the injection component 1. The medicament 5 is unable to escape, and the entire reservoir 4, therefore, moves with the cap 11 and the bar 12. When the sharp beveled end 7 reaches the septum 13, it cuts off and allows the medicament 5 to flow through the hole in the discharge tube 6 and into the gap 17 in the injection component 1 in the liner 16 in Figure 3. Most of the liquid will be transferred as a result of the pressure differential between the recess 17 and the reservoir 4, and the continuous movement of the plunger 10 completes the transfer of the medicament 5. The transferred amount can be controlled by adjusting the screw cap 11 according to the volume-related marks ( not shown) on the outside of the support 4, or the piston 14 can reach a stopping position determined by a characteristic within the hole of the injection component 1 or the power unit. After the user has filled the injection component through liquid transfer from the transfer device, the entire reservoir and associated components are separated from the injection component in the brittle connection 3, as shown in Figure 7, and the full injection component is ready to join the energy union. Alternatively, the cartridge may be ready to be attached to the power unit by the manufacturer (as indicated above, the two, for example, may be integral with one another). The brittle connection 3 can be an accessory of a molding part of the injection component 1 and the support 2, or it may be a separate means of attachment, the intention is to provide a device of a trajectory with evidence of falsification to prevent misuse or abuse. Figure 2 shows an assembly similar to those already described, except that the piston 14 is initially placed at the discharge end of the injection component 1 When the medicament 5 is transferred from the reservoir, the hydraulic pressure force the piston 14 along the hole of the injection component 1 until enough liquid has been transferred. Some applications require that a lyophilized drug be reconstituted prior to injection, and Figure 3 shows an assembly similar to that shown in Figure 4, but having a pellet of the lyophilized material 18 placed within the gap 17. Here the gap serves to Keep the lyophilized material avoiding hydration. An alternative method for transferring the medicament is shown in Figures 8 and 9. An additional piston 20 is assembled in the reservoir 4a, with the medicament 5 which will be transferred contained between the pistons 20 and 10. the seal 8a need not comprise a septum , since the piston prevents the medicament 5 from flowing to the injection component 1, although the gap 17a is in vacuum connection with the gap 17. If necessary, the piston 20 is prevented from moving as a result of a differential of the piston. pressure using a stop or retainer. Referring to Figure 9, the screw cap 11 is operated to move the bar 12 and the plunger 10 towards the injection component. The medicament 5 is trapped between the pistons 10 and 20, and moves with the pistons until the moistened face of the piston 20 reaches one or more of the grooves 19 in the wall of the reservoir 4a. The piston 20 then stops as there is insufficient hydraulic pressure to move it, and the medicament 5 flows through the slots 19 and towards the injection component. 1 . The tank and the associated parts are then separated as previously described and the injection component is ready for use.

Claims (17)

1. - A needleless injector cartridge, comprising: an injection component defining a gap therein for receiving the medicament, and having an injection discharge orifice communicating with the gap; and a transfer device comprising a reservoir containing liquid, and transfer means for causing the liquid to flow from the reservoir, through a reservoir outlet, into said recess.

2. A cartridge according to claim 1, wherein said transfer means are arranged to cause the liquid to flow into said gap through the discharge orifice.

3. A cartridge according to claim 2, wherein the transfer device comprises a support connected to the injector component, the tank is movably mounted on the support for movement towards the injection component, and said transfer means comprise a mounted piston for movement towards the tank outlet.

4 .- A cartridge according to claim 3, comprising a septum, which, in an unperforated state, provides a barrier to the flow of liquid into the gap, the tank outlet being defined by means provided with a member Septum perforation.

5. A cartridge according to claim 3, wherein the transfer means further comprise a second piston, with the liquid initially being maintained between the two pistons, and at least one fluid path allowing the fluid to escape between the two pistons towards the reservoir outlet once the pistons have arrived. to a predetermined position.

6. A cartridge according to any of claims 3 to 5, wherein the transfer means comprise a screw cap that can be rotated by a user to cause the sliding movement of the piston.

7. A cartridge according to claim 6, wherein the screw cap has an internal screw thread, which couples an external screw thread formed on the support.

8. A cartridge according to any of claims 2 to 7, wherein the recess is in a condition substantially evacuated before the liquid flows therein.

9. A cartridge according to any of claims 2 to 8, wherein the gap initially contains a medicament in lyophilized form, and the liquid is a liquid suitable for reconstituting the drug from its lyophilized form to an injectable form.

10. A cartridge according to any of claims 2 to 9, wherein the injection component has a piston therein, which is initially located adjacent to the discharge orifice, the piston being adapted to move away from the orifice in response to the flow of liquid through the tank outlet.

11. A cartridge according to any of claims 2 to 8, or claim 10, wherein the liquid is a liquid drug in injectable form.

12. A cartridge according to any of claims 2 to 10, wherein the injection component and the transfer device are connected through a brittle connection.

13. A cartridge according to any of the preceding claims, wherein said tank is made of glass.

14. - A cartridge according to any of the preceding claims, wherein said gap is defined by a plastic member.

15. A cartridge according to any of claims 1 to 13, wherein the gap is defined by a liner surrounded by an external member.

16. A needleless injector comprising a cartridge according to any of the preceding claims, mounted on a driven.

17. A needleless injector according to claim 16, wherein the cartridge and the actuator are integral with each other.