EP3866888A1

EP3866888A1 - Passive injection device with automatic securing means

Info

Publication number: EP3866888A1
Application number: EP19784091.1A
Authority: EP
Inventors: Roland Cherif-Cheikh; Tabatha BOURGOIS; Lluis PARETA BELTRAN; Frederic Lacombe; Laurence Lachamp
Original assignee: Edix Sa
Current assignee: Edix Sa
Priority date: 2018-10-16
Filing date: 2019-10-15
Publication date: 2021-08-25
Also published as: WO2020079012A1; FR3087129A1; CA3116027A1; US20210393889A1; AU2019362327A1; FR3087129B1

Abstract

The present invention relates to an injection device, comprising a cylindrical body (3) enclosing a tank (9) containing a product to be injected, which is slidably mounted in the body (3), which is open at one end on an injection needle (11) and is closed at the other end thereof by a piston (16) mounted so as to be translatably movable in the tank under the action of a piston rod (17) provided with a control member (19), the surface of the distal end (3a) of the body (3) being coated with adhesive means capable of ensuring that said surface is held on the skin (4) of a patient. Said device is characterised in that it comprises means for securing the needle which are activated by the adhesive means when a withdrawal force is exerted on the injection device.

Description

PASSIVE INJECTION DEVICE WITH AUTOMATIC SAFETY

The present invention relates to a passive safety injection device for enabling an increased stability of its positioning during injection 0t Uno MISO øn prot0Ction to131ø 0t autorna11puø its aiguill0 d0 ^ d _^ injoction before laying the bone AP ^f inj0ction

Such a safety device is said to be passive because on the one hand its operation is entirely independent of the way in which the user operates to carry out the injection and on the other hand the latter cannot carry out operations or errors that would prevent it from starting, for example not going after an injection before withdrawing the needle.

By total protection of the needle is meant that the needle can be kept in an aseptic or sterile environment without contact with the outside until it is implanted at the injection site.

Such a passive safety injection device can be applied to all injection devices and in particular to conventional syringes with a smooth piston rod activated in translation. It can also be applied to screw injection devices, with a threaded piston rod activated in rotation.

We also know that for medical and nursing specialists, an injection is done by translation, while for the whole population, this gesture is much less common, natural and simple than rotation. Indeed, injection in translation is an atypical gesture that is never performed in everyday life, this gesture requiring precise positioning of three fingers. This translation can give the patient the impression to introduce something into his body by moving the pressure thumb towards the skin. This gesture performed without fixed support poses a stability problem which causes movements of the implanted needle and thwarts the precision of the dosages. This gesture is sensitive to the pressure received in return, which can be perceived as variable, which therefore makes it difficult to perform at constant speed from start to finish. Finally, in this unstable holding position, breaks during the injection depending on the pain experienced are difficult to achieve.

The rotational injection takes up a usual gesture performed daily in everyday life, which can be performed without precise positioning with different fingers, even with the hand. This rotation avoids the impression of introducing something into his body and drastically reduces the pressure on the skin. This gesture is performed with a fixed support which stabilizes the device and the needle, is not sensitive to pressure and is naturally performed at constant speed. In this stable holding position, breaks based on perception are easy to achieve.

Another constraint linked to injections, especially when the latter are carried out by non-specialists and involve viscous or pasty products, is to know when the entire dose has been injected. Faced with this uncertainty, the tendency is to press very hard at the end of the injection, causing pain by the pressure and the movements of the needle in the tissues.

In addition, with translational injections, the visibility of the piston at the bottom of the syringe reservoir very close to the injection point is always difficult, while with rotational injections, it is impossible to force the pressure and the we can have a breakpoint precise and visible from the rotation which signals the end of the injection. In addition, the graduations can be transferred higher on the body of the device where they are much easier to read than at the base, in contact with the skin.

In the case of self-injectors in pressure translation, these devices exert strong pressure on the skin, which is difficult to compatible and poorly tolerated by patients, especially for children and the elderly, for whom this represents a real sensation of blow or shock.

The object of the present invention is to propose a means of stabilizing the distal part of an injector device which comes into contact with the skin of a patient to be treated, such stabilization favoring the use of an injection device. by rotation of a control member. Of course, such a stabilization means is also advantageous for the implementation of any other injection device, in particular by translation.

The present invention also aims to provide an injection device by rotation requiring to implement it with only one hand of the user.

Furthermore, with regard to safety, injection devices are known which are provided with mechanisms making it possible, once the injection operation has ended, to retract the injection needle inside the body of the device. , thus avoiding any risk of accidental puncture to the user. However, injection devices of this type which, most of the time, use spring mechanisms, prove to be of great complexity which generally results in high cost prices.

There are thus known from patent applications US 2003/212362 and WO 2004/032989 injection devices whose stability is ensured on the body of a patient at using adhesive means arranged on their distal end and which moreover comprise means making it possible to ensure, after the injection, that the needle is secured. Such systems are made up of complex mechanical means which have the drawback of using elements liable to generate jerks during the administration of the products to be injected which risk exerting stress on the needle introduced into the patient's body, which can lead to injury and pain.

Finally, document WO 2015/048791 discloses an injection device able to optionally have adhesive means on its distal part which make it possible to stabilize it on the skin of a patient. However, such a device does not have passive means making it possible to automatically protect the syringe throughout the injection phase and after it.

The object of the present invention is to propose a safety injection device which is simple and consequently easier and less expensive to produce and which, moreover, does not present the risk of injuring the patient during the injection.

The present invention thus relates to an injection device of the type comprising a cylindrical body containing a reservoir containing a product to be injected, which is slidably mounted in the body, which open at one end on an injection needle and which is closed at its other end by a piston mounted movable in translation in the reservoir under the action of a piston rod provided with a control member, the surface of the distal end of the body being coated with adhesive means capable of ensuring maintaining this surface on the skin of a patient, characterized in that it comprises means for securing the needle, the activation of which is ensured by the adhesive means when a withdrawal force is exerted on the injection device.

The control member may consist of a cylindrical cap which will be slidably mounted on the body, the piston rod being secured by its proximal end to the bottom of this cap and passing through an element mounted to move in translation in the cap.

This movable element may consist of a nut into which the piston rod will be screwed or of a drawer in which the piston rod will be slidably mounted.

The proximal end of the reservoir may be secured to said element and may include at least one deformable tongue which will extend towards the bottom of the cap and will end in a radial boss extended by a bevel.

Furthermore, the distal face of the element may include a circular groove of a shape complementary to that of the bevel of the deformable tongue so as to receive the latter when the element is applied against the proximal face of the body and to deform it. towards the longitudinal axis of the latter.

The internal face of the cap may include a first proximal circular stop whose distal face will be perpendicular to the axis of the body, and a second distal circular stop of rectangular section perpendicular to the axis of the body.

The height of the circular stops may be such that, when the element is applied against the proximal face of the body, the deformation of the tongue will allow the passage of the radial boss to the right of the latter during a displacement of the cap relative to the body. This height of the circular stops may be such that, when the element is not applied against the face proximal to the body, the tongue will be released and its radial boss will abut against the distal face of the proximal circular abutment and abut against the proximal face of the distal circular abutment when the cap is moved relative to the body.

According to the invention, in the rest position, or not in use, the distal surface of the body coated with adhesive means may be protected by a removable membrane.

The present invention also relates to an injection device of the type comprising a cylindrical body containing a reservoir containing a product to be injected, which is open at one end on an injection needle and is closed at its other end by a mounted piston movable in translation in the reservoir under the action of a control member, characterized in that the surface of the distal end of the body is extended by a boss.

This boss may be of planar shape and substantially perpendicular to the longitudinal axis of the body or be of convex shape.

An embodiment of the present invention will be described below, by way of non-limiting example, with reference to the appended drawing in which:

FIG. 1 is a view in axial and longitudinal section of an embodiment of an injection device according to the invention shown in the rest or pre-injection position,

FIG. 1a is an enlarged view of zone A of the injection device as shown in FIG. 1,

FIG. 2 is a perspective view of the injection device shown in FIG. 1 before the injection phase, FIG. 3 is a view in axial and longitudinal section of the injection device of FIG. 1 shown during injection,

- Figure 3a is an enlarged view of area B of the injection device as shown in Figure 3, Figure 4 is an axial and longitudinal sectional view of the injection device of Figures 1 and 3 shown once injection finished,

Figure 5 is an axial and longitudinal sectional view of the injection device of Figures 1 to 4 shown after injection once put in the safety position.

FIG. 5a is an enlarged view of zone C of the injection device as shown in FIG. 5.

- Figures 6 to 9 show a second embodiment of an injection device according to the invention, in which the injection is carried out by means of translation, respectively in the rest position, during injection, at the end of injection and in the safety position, FIG. 10 is an alternative embodiment of the injection device according to the invention.

FIGS. 1 to 5 show an embodiment of an injection device according to the invention of the type in which the injection is carried out by means of rotation.

This injection device 1 comprises a tubular body 3 which is hollowed out by an axial cylindrical conduit 5 which opens into a cylindrical distal chamber 7 of larger diameter. The conduit 5 receives a reservoir, constituted in this embodiment, by a syringe 9 containing the product to be injected which ends in an injection needle 11. The distal end of the syringe 9 is provided with a seal sealing ring 12 which is embedded in a bowl 10 of the body 3, and the length a of chamber 7 is such that, in the rest position, or pre injection, as shown in FIG. 1, the injection needle 11 is housed inside the chamber

7.

The proximal end 3b of the body 3 ends in two diametrically opposite hooking tabs 14 which themselves end in an external boss 14a of height H followed by a bevel 14b, these tabs being made deformable by the presence of an internal space 15.

A piston 16 is slidably mounted inside the syringe 9 under the action of a threaded piston rod 17. The proximal end of this piston rod is integral with the bottom of an actuating member consisting of a cylindrical cap 19 whose internal diameter D is slightly greater than that of the body 3 increased by the height H of the two stops 14a , so as to allow the cap 19 to slide on the body 3. There is thus D = d + 2xH. In the rest position, as shown in FIG. 1, the distal end of this cap 19 is slightly engaged on the body 3 so as to favor the guiding of the latter.

The internal face of the cap 19 comprises a first circular distal stop 26 of height h, of rectangular section, intended to keep the body 3 blocked in the cap 19 during the withdrawal of the needle from the body 4 once the administration of the product has ended. . Finally, the internal face of the cap also includes a second circular proximal stop 25 of height h, the proximal face 25a is preferably inclined and the distal face 25b is radial, and spaced from the first stop 25 by a distance equal to the width of the boss 14a, and which is intended, as explained below, to prevent a second exit of the needle 11 once the injection phase is complete. A cylindrical nut 21, of thickness e _ ^ _ forming a stopper is screwed onto the piston rod 17 and comprises a cup 20 in which the proximal end of the syringe 9 is fixed. The periphery of the distal face of the nut 21 is hollowed out by a circular groove 23 of shape complementary to that of the bevel 14b of the deformable tongues 14. The diameter b of this nut 21 is slightly less than the internal diameter D of the cap 19 at which the heights H of the two bosses 14a have been cut off. We thus have b = D - 2xH.

The distance c which exists, when the injection device is at rest, as shown in FIG. 1, between the proximal end 3b of the body 3 and the distal face of the nut 21 makes it possible to control the distance whose injection needle 11 will emerge from the distal face 3a of the body 3 during the injection, as explained below.

This distal face 3a of the cylindrical body 3 can be formed by the annular surface of the body 3 or, as in the embodiment shown in FIG. 2, include an extension part 3c which is flat and perpendicular to the longitudinal axis xx 'of the injection device, making it possible to increase the size of this surface.

According to the invention, the latter is coated with an adhesive capable of allowing adhesion with the skin 4 of the patient to be treated, this adhesive being protected in the non-use position, by a film or a film 27. sticky surfaces based on silicone, acrylate, polyacrylates, or any other known copolymers used in the adhesive surface composition for medical devices, such as, for example, dressings, ostomy bags, electrodes and electro-surgical plates, patches or even hair prostheses. In an alternative embodiment, the extension part 3c can be non-planar and in particular be convex in shape as shown in FIG. 10.

Thus, during the implantation of the needle in the patient's body, the deformation of the surface of the skin by sinking will better adapt to the whole of the sticky surface, better adhere to it and better fix the device to its injection site. At the end of the injection, a simple movement perpendicular to the surface of the skin around the needle will make it possible to withdraw the injection device, thus avoiding pendulum movements which are likely to move the needle in the body. This perpendicular withdrawal will also facilitate the detachment of this adhesive surface: the skin located more on the periphery of said sticky surface will peel first and thus gradually to the part closest to the needle.

This non-planar sticky surface which will prevent detachment of the entire surface at the same time after injection makes it possible to increase the bonding force without its removal being difficult or painful. This upward and progressive movement of the skin at the time of withdrawal of the needle also avoids the usual bleeding at the injection site linked to a phenomenon of suction of the needle in the opening which it made in the tissues. By pulling the skin back when withdrawing said needle, this sticky surface system compensates for this suction phenomenon and ensures that the opening closes without causing a resurgence of blood.

It will be noted that in the injection device according to the invention, the adhesive surface has two functions.

A first function, known from the prior art, is to stabilize the injection device by relative to the patient's skin so as to prevent slipping during the injection phase.

A second function, as explained in detail below, is to control the activation of a mechanism for securing the injection device when the user exerts on it a pulling force intended to remove it of the patient's body, which makes this automatic locking, and this without the user having any additional action whatsoever to perform.

Under these conditions, the operation of the injection device according to the invention is established as described below.

After removing the protective film 27, the user brings the adhesive distal end of the injection device into contact with the area of the patient's body, where he wishes to perform the injection. Consequently, this end of the injection device, due to its adhesion with the injection zone, is stabilized.

Then, the user exerts a linear thrust on the cap 19 in the direction of the arrow F until the nut 21 abuts with the proximal face 3b of the body 3, which has the first effect of bring out the injection needle 11 from the injection device and introduce it into the patient's body 4, as shown in FIG. 3. On the other hand, at the end of this translational movement, the bevels 14b tongues 14 penetrate into the groove 23 of the nut 21, which has the effect of deforming the tongues 14 inwards and ensuring a rotational connection of the nut 21 with the body 3. In addition, in due to the inward deformation of the tongues, these are released and able not to block the movement of the cap when, during injection, they will reach the level of the circular stops 25 and 26. The injection device is therefore ready to inject the treatment product.

To do this, the user rotates the cap 19, which he can moreover do with one hand due to the connection existing between the distal part 3a of the body 3 with the patient's body 4 which is ensured by the adhesive product. During this rotation of the cap 19, the piston rod 17 is screwed into the nut 21, and the latter being immobilized in rotation relative to the body 3, the piston 16 moves in the syringe 9 and administers the treatment product in the patient's body until the plunger reaches the neck of the syringe 9, as shown in Figure 4, or the user stops his inj ection.

Once the injection has been carried out, the user pulls on the cap 19 in the opposite direction to the arrow F. During this movement of withdrawal of the injection device, the distal face 3a of the latter being held in adhesion with the patient's skin, the nut 21 is brought back so that the tabs 14 are then released and return to their initial position.

The withdrawal movement takes place until the proximal face 25a of the stop 25 comes into contact with the boss 14a and the latter falls into the free space between the two stops 25 and 26 as shown in the Figures 5 and 5a.

Therefore any relative movement of the cap 19 relative to the body 3 in the direction of the arrow F or reverse is no longer possible and the injection device is thus locked and secured against any subsequent use.

It is understood under these conditions that it is the second function exercised by the means for bonding the end distal of the injection device on the patient's skin which has the effect of controlling the actuation of the safety device during the withdrawal phase.

Such an arrangement is particularly interesting for several reasons. Firstly, it makes it possible to produce a safety injection device in a particularly simple way in comparison with the prior devices of the state of the art which use complex mechanisms and which, consequently, are of particularly difficult manufacture, which makes them more expensive.

Secondly, this arrangement makes it possible to trigger the means capable of securing the injection device in safety by a withdrawal movement of the latter, in contrast to the prior devices in which the safety is obtained by a movement. pressure on the patient's body which occurs in an area close to the injection site. We know that this kind of pressure is likely to cause the risk of bleeding or bruising.

By continuing the withdrawal movement, the user removes the distal face of the injection device from the surface of the patient's skin by blocking the body 3 relative to the cap 19 against the second distal stop 26.

Of course, and although the present example is described with regard to a small volume syringe, in particular of the insulin type, it can be adapted to any other device using syringes or cartridges, standard or not, than this. either according to an injection mode controlled by rotation as described in this example or according to injection modes controlled in translation with conventional syringes using smooth plunger rods and finger rests. In such a version with a smooth piston rod actuated in translation, the cap 19 could be replaced by two arms also integral with the piston rod. These two arms could circulate in two windows inside the finger rest. As for the screw version, the implantation of the needle would be done by exerting a push of these two arms in the direction of arrow F.

Furthermore, the safety means implemented in the present injection device also have the advantage of being able to replace the cap which usually covers the injection needle. This eliminates an operation of removing the cap which is dangerous because it exposes the user to the cutting bevel, that moreover it can damage the injection needle and that finally it involves risks of external contamination of this needle before its inj ection.

In a variant implementation of the invention and as shown in FIG. 10, the body 3 may include a window 28 which will extend along the syringe and which will make it possible to check its content before use.

Furthermore, and according to the invention, a label can connect the body 3 to the cap 19 so as to ensure the relative maintenance of these two parts before injection. Such a label will also allow vé2G1f10 before use the integrity of the sealing of the injection device. This label may include a precut line promoting its rupture during the injection.

Of course, the passive injection device with automatic safety device according to the invention is not limited to the mechanisms described above and could be applied to any other type of mechanism in which the function of triggering of the safety means would be ensured by bonding its distal part to the patient's skin.

One could for example in particular apply the present invention to an injection device in which the injection would take place not by rotation, as described above, but by translation.

There is shown in Figures 6 to 9 such an injection device for which we will keep the notations and references used in the previous example.

This injection device has the following essential differences with the previous device.

First of all, it comprises a piston rod 17 'which consists of a smooth non-threaded rod which is slidably mounted in an axial bore of a drawer 2' with a level of friction fj. The drawer 21 'is mounted in turn movable in translation in the cap 19 with the lowest possible level of friction f ₀ . This drawer has at its proximal end a circular groove 23 of the same type as that of the nut 21 of the previous example.

As before, and as shown in FIG. 6, after having removed the protective film 27, the user brings the adhesive distal end of the injection device into contact with the area of the patient's body, where he wishes to perform the 'injection. Consequently, this end of the injection device, due to its adhesion with the injection zone, is stabilized.

Then, starting from the rest position shown in FIG. 6 and as shown in FIG. 7, the user exerts a linear thrust on the cap 19 in the direction of the arrow F. It will also be noted that we will make sure that the friction level fi is higher than the friction level necessary for the deformation of the tongues 14 by the circular groove 23 of the drawer 21 'added to the level of friction between the O-ring 12 and the body of the syringe 9. We will have: fi _> f ₂ + f ₃

Under these conditions, the translational movement exerted on the cap 19 has the first effect of bringing the injection needle 11 out of the injection device and introducing it into the patient's body 4, as shown in the Figure 7. On the other hand, at the end of this translational movement, the bevels 14b of the tongues 14 penetrate into the groove 23 of the drawer 21 ', which has the effect of deforming the tongues 14 inwards as well as was in the previous example.

The injection device is therefore ready to inject the treatment product.

To do this, the user continues his axial movement in the direction of the arrow F so that the piston 16 moves in the syringe 9 and administers the treatment product into the patient's body until the piston reaches the neck of the syringe 9, as shown in Figure 8, or that the user stops his inj ection.

Once the injection has been carried out, the user pulls on the cap 19 in the opposite direction to the arrow F. Consequently, the injection means are secured as described above.

Claims

1. - Injection device of the type comprising a cylindrical body (3) containing a reservoir (9) containing a product to be injected, which is slidably mounted in the body (3), which is open at one end on a needle d injection (11) and is closed at its other end by a piston (16) mounted movable in translation in the tank under the action of a piston rod (17) provided with a control member (19), the surface of the distal end (3a) of the body (3) being coated with adhesive means capable of maintaining this surface on the skin (4) of a patient, characterized in that it comprises means for placing safety of the needle, the activation of which is ensured by the adhesive means when a withdrawal force is exerted on the injection device.

2. - injection device according to claim 1 characterized in that the control member consists of a cylindrical cap (19) which is slidably mounted on the body (3), the piston rod (17) being secured by its proximal end to the bottom of this cap (19) and passing through an element (21, 21 ') mounted movable in translation in the cap.

3. - Injection device according to claim 2 characterized in that the movable element consists of a nut (21) in which is screwed the piston rod (17).

4. - Injection device according to claim 2 characterized in that the movable element consists of a drawer (21 ') in which the piston rod (17') is slidably mounted.

5. - Injection device according to any one of the preceding claims, characterized in that the proximal end of the reservoir (9) is secured to the element (21, 21 ').

6. - injection device according to any one of the preceding claims, characterized in that the proximal end (3b) of the body (3) comprises at least one deformable tongue (14) which extends towards the bottom of the cap ( 19) and ends with a radial boss (14a) extended by a bevel (14b).

7. - Injection device according to claim 6 characterized in that the distal face of the element (21, 21 ') has a circular groove (23) of a shape complementary to that of the bevel (14b) of the tongue deformable (14) so as to receive the latter when the element (21, 21 ') is applied against the proximal face

(3b) of the body (3) and to deform it in the direction of the longitudinal axis (cc ') of the latter.

8. - Injection device according to claim 7 characterized in that the internal face of the cap (19) comprises a first circular abutment (25) proximal whose distal face (25b) is perpendicular to the axis (cc ') of the body (3), and a second distal circular stop (26) of rectangular section perpendicular to the axis (cc ') of the body (3).

9. - injection device according to claim 8 characterized in that the height (H) of the circular stops (25,26) is such that, when the element (21, 21 ') is applied against the proximal face (3b ) of the body (3), the deformation of the tongue (14) allows the passage of the radial boss (14a) to the right of the latter during a displacement of the cap (19) relative to the body (3).

10. - Injection device according to claim 9 characterized in that the height (H) of the stops circular (25,26) is such that, when the element (21, 21 ') is not applied against the proximal face (3b) of the body (3), the tongue (14) is released and its radial boss ( 14a) abuts against the distal face of the proximal circular abutment (25) and abuts against the proximal face of the distal circular abutment (26) when the cap (19) is moved relative to the body (3).

11. - injection device according to any one of the preceding claims, characterized in that, in the rest position, or not in use, the distal surface (3a) of the body (3) which is coated with adhesive means is protected by a removable membrane.

12. - Injection device of the type comprising a cylindrical body (3) enclosing a reservoir (9) containing a product to be injected, which is open at one end on an injection needle (11) and is closed at its other end by a piston (16) mounted movable in translation in the reservoir under the action of a control member (19), characterized in that the surface of the distal end (3a) of the body (3) is extended by a boss (3c).

13. - injection device according to claim

12 characterized in that the boss (3c) is of planar shape and substantially perpendicular to the longitudinal axis (cc ') of the body (3).

14. - Injection device according to claim 12 characterized in that the boss (3c) is of convex shape.