FR2604363A1 - DEVICE FOR INJECTING SUBSTANCES, ESPECIALLY MEDICINAL PRODUCTS - Google Patents

Abstract

The device comprises a first sliding container (2) which forms a first chamber closed by a piston (3) and containing the solubilization liquid. A second container (6) slides before the first container and forms a second chamber filled with spheres or particles coated with the dry medicinal substance. By actuation of drive means (2), a double needle (12) makes both chambers communicate through perforable membranes (4, 8), thereby causing the transfer of liquid from the first chamber to the second chamber and its advance through the interstices in the second chamber for a rapid and homogeneous dissolution of the medicinal substance injected by the injection needle.

Description

Device for injecting substances, especially medicinal substances.

 The present invention relates to a device for injecting substances and in particular medicinal substances. The device is more particularly intended to allow self-injection, or a very rapid injection, of an active ingredient whose stability is poor in the dissolved state in the injection liquid.

 A large number of medicinal substances intended to be administered by transcutaneous injection have little or reduced stability when they are dissolved or dispersed in the solvent suitable for injection. These substances should be stored in a dried or freeze-dried state or, sometimes, in a moist but concentrated state. To carry out the injection, the liquid injection vehicle is then transferred, generally by means of a syringe, by piercing a cap of the container or bottle, in contact with the dry substance to dissolve it, after which draw the dose thus formed into the syringe to proceed with the injection.

 These operations are complex and require a certain handling time including a dissolution time which can be variable depending on the substances. This time is a gene in an emergency, even for specialized personnel.

 A fortiori, such a delay cannot be envisaged in the case where one must normally use syringes, as for example in the case of protection of soldiers or civilians in the event of chemical or biological aggression without forget that the major part of the subjects can only awkwardly implement the aforementioned complex operations themselves.

 The present invention proposes to remedy these drawbacks and allow rapid administration by injection, if necessary by self-injection, of medicinal substances stored in the dry state or at least concentrated.

 The subject of the invention is a device for the injection or self-injection of medicinal substances, characterized in that it comprises, in combination, a first chamber, containing a liquid vehicle, a second chamber containing, disseminated in the chamber, at least one drug substance to be dissolved or diluted, said second chamber being arranged internally so as to be traversed by the liquid vehicle coming from the first chamber, means being provided for expelling the liquid from the first chamber and bring it through the second chamber following scattered paths ensuring the rapid dissolution or dilution of the drug substance, the liquid leaving the second chamber being immediately injected by an injection means, such as for example a needle.

 According to an advantageous characteristic of the invention, the free volume in the second chamber is significantly less than the volume of liquid intended to pass through it.

 In accordance with the invention, the path provided for the liquid in the second chamber is designed to avoid a direct passage through the second container between an inlet and the injection outlet, and on the contrary to cause the liquid to come into contact with the drug substance contained in said second chamber.

 In a particularly preferred embodiment of the invention, the second chamber is filled with solid particles, such as beads, fibers or the like, between which the drug substance to be dissolved is placed so that the liquid coming from the first chamber is forced to distribute and travel through the interstices formed by the accumulation of beads, and to gradually and quickly dissolve the drug substance between the beads.

 Preferably, the beads or particles are coated with the dry or concentrated drug substance.

 As a result, it is possible to practically dissolve all of the drug substance with a relatively small volume of liquid, as provided for the administration of a dose of drug, and this by minimizing the volume of air. contained in the first chamber, air which risks being injected at the start of injection, in particular in the case where the device is of the self-injection type.

 Advantageously, the device according to the invention can use conventional components by providing, in a preferably elongated body, a first sliding container in the shape of a syringe body with a plunger or similar means at the rear to form the first chamber. containing the liquid, a second container, possibly sliding, of non-variable volume disposed in front of the first container, said second container forming the second chamber, sterile means such as needle means being provided to allow, during actuation of 'Motor means on the piston of the first container, the communication of the liquid leaving the first container with the second container.

 Thus, for example, the end of the first container opposite the piston can be closed by a perforable membrane, as well as the rear end of the second container, a needle with two points being disposed between the two perforable membranes to perforate said membranes when the drive means, at first, pushes the first container towards the second before moving the piston in the first container.

 Alternatively, such a transfer needle, which can then be a single point, is permanently carried either by the front end of the first container, or by the rear end of the second container.

Other advantages and characteristics of the invention will appear on reading the following description, given by way of nonlimiting example and referring to the appended drawing in which:
Figure 1 shows a schematic view of first embodiment of the device;
Figure 2 shows a schematic view of a second embodiment of the device.

 The device according to the invention represented in FIG. 1 is of the self-injecting type and one can refer to the description of French patent 81.13737 published under nv 2.509.615, filed on July 15, 1981, for the detail of an actuating mechanism making it possible first of all to propel a syringe forward which can, for example, be used as a first container to form the first chamber, then let the liquid contained in the syringe exit through the front end this one.

 The device according to the invention comprises, in a tubular body 1, a motor device 18 of the type described in the aforementioned patent.

 In the tubular body 1 are successively mounted, so as to be able to slide from rear to front, a first container 2 of cylindrical shape provided at its rear end with a piston 3 capable of sliding in the container 2 and at its anterior end of a waterproof rubber seal forming a perforable membrane 4, so as to delimit a first chamber 5 filled with a liquid vehicle intended to dissolve the drug substance, and a second container 6, also of cylindrical shape, the volume of which internal is invariable, this second container 6 having at its anterior end an injection needle 7 in communication with the interior of the container 6 and, at its rear end, a perforable rubber membrane 8, to delimit a second chamber 9 of which sees that it is completely filled with glass beads 10.

 The diameter of these glass beads is preferably between 0.5 and 2.5 mm.

 Other materials than glass can be used, in particular plastic or synthetic materials. The particles can also have shapes other than that of spherical beads.

 These beads 9 are coated or covered with the lyophilized drug substance intended to be administered.

 Between the membranes 4 and 8, there is disposed a sliding part 11 carrying an axial needle 12 emerging on either side of the part 11 and bevelled at each of its two ends.

 The device is, at rest, in the position shown in FIG. 1, this position being able to be maintained, for example, by a weak spring recalling the container 6 in the recessed position in which the needle 7 does not emerge from an anterior opening 13 made in the tubular body 1.

 The operation is as follows.

 When the injection must be carried out, the user applies the anterior end, with the opening 13 of the body 1, against the body part and actuates, in a manner known per se, the motor means 18.

This exerts a forward thrust which moves the container 2 forwards. .The forward movement causes, in an order of succession, or simultaneously, depending on the resistances and friction selected, the perforation of the membranes 4 and 8 by the needle 12 and the forward movement of the second container 6 and therefore , the introduction of the needle 7 into the body part at a time when the two chambers 5, 9 have just been brought into communication by the needle 12. Once the container 6 has arrived at its front position, the thrust of the action of the drive means 2, causes the piston 3 to move in the container 2, which quickly drives the liquid 5 through the needle 12 into the volume 9. In the latter, the liquid is distributed uniformly in the path complex formed by the interstices between the balls, which ensures rapid and uniform dissolution of all of the substance carried by the balls.

 Where appropriate, means can be provided to avoid a risk of fragmentation of certain balls 10 by the needle 12, this can for example be achieved by an adequate conformation of the internal face of the perforable membrane 8.

 Referring to Figure 2, we see an alternative embodiment in which the part II carrying the needle 12 is replaced by a part 14, crossed by the needle 12, this part 14 being integral with the container body 2 which it forms the front wall, a thin membrane 15 which can be perforated during the increase in pressure caused by the displacement of the piston 3, preventing, in the idle state, the liquid 5 from passing through the needle 12.

 The second container 6 also has a front wall 16 crossed by an injection needle 17 bevelled at its two ends, an internal membrane 18, similar to the membrane 15 preventing, in the state of rest, communication between the second chamber 9 inside the second container 6 and the needle 17, this membrane being displaced and perforated when the liquid arrives.

 This embodiment avoids the need to cover the injection needle with a sealed cap and therefore avoids the prior manipulation consisting in removing the cap.

 The coating or covering of particles, such as glass beads 10, with the drug substance can be carried out either inside the container 6 or outside, with subsequent filling of the various containers 6 of a manufacturing batch . The product can be deposited in different ways on the surface of the beads or particles, for example by lyophilization in situ, by dusting, coating, mixing, etc.

 Provision may also be made to mix particles coated with different substances having an incompatibility with one another, preservation in the dried state eliminating the denaturation resulting from the incompatibility which would appear in the liquid phase.

 Of course the liquid 5 can itself also contain, in solution, another active substance.

 Instead of being coated or covered with dry substance, the particles could also be moistened with a concentrated solution or suspension of an active substance which will be entrained by the liquid vehicle during the injection.

 It is also understood that the volume of air initially located in the chamber 9, and which is equal to the difference between the internal volume of the chamber and the sum of the volumes of the beads and of the substance, is small, without being for that null because it must authorize at the start a path of the liquid authorizing the obtaining of a relatively regular concentration during the major part or the whole of the injection.

 In another embodiment of the invention, the balls can be replaced by other filling means, such as for example grids, lattices, fabrics, or other non-particulate structures capable of both maintaining a substantially homogeneous spatial distribution of the active substance before dissolution and to force the liquid which crosses the second chamber to travel, without preferential route, through the entire volume offered.

 Although the invention has been described in relation to a particular embodiment, it is understood that it is in no way limited thereto and that it is possible to make any modifications to it in shapes or materials without thereby distance neither from his frame nor from his mind.

Claims (8)

 1. Device for the injection or self-injection of medicinal substances, characterized in that it comprises, in combination, a first chamber (5) containing a liquid vehicle, a second chamber (9) containing, disseminated in the chamber, at least one drug substance to be dissolved or diluted, said second chamber (9) being arranged internally so as to be traversed by the liquid vehicle coming from the first chamber (5), means being provided for expelling the liquid from the first chamber and bring it through the second chamber following scattered paths ensuring rapid solubilization or dilution of the drug substance, the liquid leaving the second chamber (9) being immediately injected by an injection means (7) .  2. Device according to claim 1, characterized in that the second chamber (9) is filled with solid particles (10) between which is located the drug substance to be dissolved.  3. Device according to claim 2, characterized in that the particles (10) are coated with the dry or concentrated medicinal substance.  4. Device according to one of claims 1, 2 and 3, characterized in that said particles are balls.  5. Device according to claim 1, characterized in that the second chamber is filled with a non-particulate structure, in particular grid, fabric or lattice.  6. Device according to any one of claims 1 to 5, characterized in that it comprises, in a body, a first container (2) containing the liquid, a second container (6) containing the medicinal substance, and, between said containers, means (11, 12, 14) making it possible, when actuating a motor means (2), to put the liquid leaving the first chamber contained in the first container into communication with the second chamber contained in the second container (6) during actuation, by the motor means of a piston or similar means (3) allowing the volume of the first chamber to be reduced.  7. Device according to claim 6, characterized in that the anterior end of the first container and the posterior end of the second container are formed of perforable membranes cooperating with a needle (12).  8. Device according to one of claims 6 and 7, characterized in that the second container (6) is sliding and maintained in the rest position by a return means.