CH718909A2 - Injection device for administering a fluid medication, with a protective needle cap. - Google Patents

Abstract

The injection device 1 according to the invention for administering a fluid medicament comprises a housing, a medicament container 2 mounted at least partially in the housing, the medicament container 2 comprising a distally arranged opening, an injection needle or cannula 3 which is in fluid connection with the opening and through which the medication can be administered, a protective needle cap 4, which is pushed over the injection needle or cannula 3 and is releasably attached at its proximal end to the medication container 2, and a protective needle cap which is releasably arranged at the distal end of the housing. The removable needle protective cap also includes at least one removable sleeve 100, wherein the removable sleeve 100 includes engagement elements 101 which, when the removable needle protective cap is removed from the housing, engage the protective needle cap 4 and remove the protective needle cap 4 from the medicament container 2. According to the invention, the withdrawal sleeve 100 is a stamped and bent part made of sheet metal, in which the engagement elements 101 are at least partially worked out of the sheet metal by means of a laser.

Description

TECHNICAL AREA

[0001] The present invention relates to the field of medical injection devices, particularly those incorporating a pre-filled syringe. In particular, the invention relates to devices used to remove protective needle caps from pre-filled syringes and methods of manufacture for these devices.

BACKGROUND OF THE INVENTION

Injection systems are known from the prior art, which comprise a pre-filled syringe as a medication container. Typically, an injection needle is fixed and non-detachable at the front end of these prefilled syringes. When such injection systems are stored, the injection needle must be kept sterile and clean. This is usually done with a needle shield. A distinction is often made between two types of needle protection caps, those with a rigid outer shell (made of a stiffer plastic) and those with a soft outer shell (made of a soft elastomer), in English then rigid needle shield (RNS) or called soft needle shield (SNS). What both types have in common is that they are sleeve-shaped with a closed front end and an open rear end. The needle protection caps are pushed over the injection needle during production. When pushed on, the transition area from the syringe to the injection needle and a soft area at the rear open end of the needle protective cap form a sterile barrier and thus protect the injection needle from contamination with germs and dirt, among other things.

When assembling the pre-filled syringe in an injection system, care must be taken to ensure that the sterile barrier described is not damaged. However, in order to be able to ensure problem-free functionality of the injection system, a device must also be provided in the injection system which can ensure the removal of the needle protective cap, regardless of the type.

[0004] In the following, auto-injectors are discussed as injection systems by way of example, but this is by no means to be interpreted as restrictive. The person skilled in the art is aware of enough other systems which could be used as an alternative at this point. Auto-injectors are typically in the form of a pen and are used for self-medication of a single injection of medication, which is to take place automatically. During the injection process, the injection needle can also be inserted into the tissue automatically, or the person using it can insert the injection needle manually.

Alternatively, the injection system could also be a safety syringe, or any other injection device, in particular a pen-shaped injection device for dispensing a single dose or multiple doses.

Before the injection process, the needle cap is removed manually. For this purpose, a needle protective pull-off cap is arranged at the front end of the typical autoinjector. The needle protection cap is pushed into the needle protection detachable cap when the auto-injector is installed and remains in this position until the auto-injector is used.

The needle guard pull-off cap comprises engagement elements which, when removing the needle guard pull-off cap from the autoinjector immediately before use, engage an outer surface of the needle guard and remove the needle guard together with the needle guard pull-off cap from the typical auto-injector. One of the challenges in designing the engagement elements mentioned is that they must engage securely in the surface of the needle protective cap when the needle protective cap is pulled off.

[0008] WO18018165 A1 discloses a needle guard pull-off cap 20 in which a remover element 25 is arranged in a movable but non-detachable manner. Remover element 25 is sleeve-shaped and encloses needle protective cap 17 at least partially in the stored state. The remover element 25 comprises the arms 29, at the free ends of which an engagement element 26 is arranged (see in particular Figures 1 and 2 of WO18018165 A1). Engagement elements 26 are now used to engage on a surface of the needle protective cap when removing the needle protective cap 20 from the injection device and take the needle protective cap with it and remove it from the injection device. The remover element is disclosed as a stamped and bent part, which has other useful elements.

[0009] US20180344947 also discloses a protective needle cap for an injection device. In this case, the remover element is more disc-shaped and also has arm-shaped elements, the free ends of which engage in a surface of the needle protective cap when it is pulled off. The remover element is manufactured either using stamping technology or using laser processes.

Stamping and bending processes have the advantage that the remover element can be brought into complex geometries and complex elements on complex geometries are also possible. However, the punching tools used allow only limited control of the sharpness of the edges on the engagement elements, which plays a central role in the process of removing the needle protective cap and must ensure secure engagement.

[0011] Laser technologies for producing the remover element, on the other hand, can lead to more defined edge sharpness. However, laser technologies are potentially expensive for large quantities, and a pure laser process would also be slow compared to stamping and bending (cycle time!).

There is therefore a need for advantageous combinations of the known production methods for the remover elements, which can ensure reliable engagement of the engagement elements in the needle protective cap.

The term "product", "medicament" or "medicinal substance" in the present context includes any free-flowing medical formulation which is suitable for controlled administration by means of a cannula or hollow needle into subcutaneous or intramuscular tissue, for example a liquid, a solution, a gel or fine suspension containing one or more medicinally active ingredients. Thus, a medicament may be a single active ingredient composition or a premixed or co-formulated multiple active ingredient composition from a single container. The term includes in particular medicines such as peptides (e.g. insulins, insulin-containing medicines, GLP 1-containing and derived or analogous preparations), proteins and hormones, biologically derived or active substances, substances based on hormones or genes, nutritional formulations, enzymes and other substances in solid (suspended) or liquid form. The term also includes polysaccharides, vaccines, DNA or RNA or oligonucleotides, antibodies or parts of antibodies as well as suitable base materials, auxiliary materials and carriers.

[0014] The term “distal” refers to a side or direction directed toward the front, puncture-side end of the administering device or toward the tip of the injection needle. In contrast, the term “proximal” designates a side or direction directed towards the rear end of the administering device opposite the end on the puncture side.

The terms injection system, injection device, injector or injection device is understood in the present description as a device in which the injection needle is removed from the tissue after a controlled amount of the medicinal substance has been released. In contrast to an infusion system, the injection needle in an injection system or in an injector does not remain in the tissue for a longer period of several hours.

The term storage condition for an injection system, an injection device or an "injector" means the condition in which the device is transferred from the distribution, the pharmacy or the treating medical care to the user, i.e. before the injection process and its preparatory actions.

PRESENTATION OF THE INVENTION

It is thus an object of the invention to provide improved or alternative injection devices which include needle guard pull-off caps whose remover elements can be configured in complex geometries and whose engaging elements include defined edge geometries. A further object of the invention is to provide methods which are useful for the production of injection devices according to the invention.

[0018] The objects are achieved by the injection device of independent claim 1 and the method of independent claim 6. Advantageous further developments result from the dependent claims, the figures and the description.

One aspect of the invention includes an injection device. The injection device comprises a housing with an axial extent from proximal to distal, in particular a pin-shaped housing. A medicament container is at least partially arranged in the housing. The injection device also includes an injection needle which is in fluid communication with the medication container. A protective needle cap is pushed over the injection needle when the injection device is in storage and is releasably fastened in the distal area of the medication unit. In advantageous configurations, the medication container and injection needle can be designed as a syringe, in which container and needle form a unit, in particular they can be designed as a prefilled syringe.

[0020] The injection device according to the invention further comprises a protective needle cap that can be pulled off. The needle protective cap can be designed in one piece or in several parts and is at least partially pushed over the needle protective cap in the storage state. However, it at least includes a (needle guard) removal sleeve. As the name suggests, the withdrawal sleeve is designed as a sleeve which extends axially from a proximal end to a distal end. The jacket wall of the sleeve is designed approximately cylindrical. In advantageous variants, the jacket wall is designed in a prismatic manner. Functional elements can be arranged on the lateral surface as well as on the proximal or distal end of the sleeve.

According to the invention, at least one engagement element is arranged on the withdrawal sleeve. The at least one engagement element is used when removing the needle protective cap from the injection device to engage in or on a surface of the needle protective cap and take the needle protective cap with the needle protective cap, whereby the needle protective cap is also removed from the injection device.

According to the invention, the withdrawal sleeve consists of sheet metal, ie in particular sheet metal. The sleeve can thus be made of strip material, for example.

According to the invention, the at least one engagement element is at least partially cut out of the metal sheet by means of a laser cutting process or laser method, so that defined edges are produced on the at least one engagement element. Due to the choice of process (laser cutting or similar laser processes), the defined edges have defined small edge radii, which can be extremely small (+0.00 mm to 0.02 mm) or even negative (where the figures given are tolerance ranges according to the design drawings). Thanks to the laser process, large quantities with consistent quality are also possible, since the laser beam does not wear out like a punching tool. The term 'defined' means according to a design specification and with consistent quality.

In an advantageous embodiment, the cut can be made at 90° to the surface (angle of the laser beam axis to the sheet metal surface), in further embodiments at a smaller angle, less than 90°, especially 30°-60° (angle of the laser beam axis to the sheet metal surface). opens up more possibilities in the design of the edges.

According to the invention, the actual shape of the sleeve as a whole is created by a stamping and bending process in which the actual lateral surface and any cover and base elements are stamped out and formed in one or more steps. In this case, the engagement element cut out by means of a laser process is contained in the lateral surface and its shape can still be adjusted by the bending steps in the stamping and bending process, but without the defined edges as such being changed, in particular being blunted.

In one aspect of the invention, the needle guard pull-off cap is designed in several parts. In this aspect, it further comprises a peel-off cap housing which has an axial extension. In this case, the withdrawal sleeve is at least partially arranged in the withdrawal cap housing. The arrangement can be fixed in one variant. In an alternative variant, the pull-off sleeve can be arranged in the pull-off cap housing so that it can move but not be detachable.

In one aspect of the invention, there are a plurality of engagement elements located on the withdrawal sleeve.

In aspects of the invention, the engagement elements are in the form of tabs, tongues or hooks and are arranged on the lateral surface of the withdrawal sleeve. The engagement elements include a fixed end which, in terms of material, merges into the lateral surface of the withdrawal sleeve, so that the engagement elements are arranged firmly on the lateral surface. Opposite the fixed end is a free end of the engagement elements. The free end can be curved relative to the rest of the engaging element, for example in a hook shape, or it can protrude straight. The engagement elements all protrude into the interior of the withdrawal sleeve.

In one aspect of the invention, the engagement elements are aligned in the distal direction and protrude obliquely into the interior of the withdrawal sleeve.

In an alternative aspect of the invention, the engagement elements are aligned in the proximal direction and bent over to form a hook at their free end. The free ends protrude diagonally into the interior of the withdrawal sleeve.

In further aspects of the invention, the engagement elements are in the form of tabs, tongues or hooks and are arranged on the outer surface of the withdrawal sleeve, with lateral limitations running between the fixed and free ends of an engagement element. Advantageously, these lateral boundaries run somewhat parallel to one another.

In yet another aspect of the invention, the free end of the engaging element can be configured with straight edges, that is, a single straight boundary. Advantageously, the straight delimitation of the free end and the lateral delimitations each merge into one another at a right angle (angles between 85° and 95° are advantageous).

In one aspect of the invention, the free end of each engagement element has sharp edges at the perimeter. The edge radii are preferably between -0.01 and +0.05 mm, particularly preferably between +0.00 and +0.02 mm.

Another aspect of the invention relates to a method for producing a withdrawal sleeve as described above in different variants. The sleeve is made in several steps, ideally from sheet metal. Preferably made of sheet metal. In one step of the method according to the invention, at least the free ends of the engagement elements and optionally the lateral boundaries are cut out by means of a laser method, the fixed ends remaining connected to the metal sheet in any case. The edges at the boundaries produced by the laser process have the desired sharp quality. In one or more stamping and bending steps, further elements and areas are stamped and bent on the sheet metal, with the sleeve being separated from the sheet metal (strip) as a whole and brought into the final sleeve shape.

CHARACTERS

In connection with the appended figures, preferred embodiments of the invention are described below. These are intended to show basic possibilities of the invention and should in no way be interpreted in a restrictive manner. Figures 1a-1d show withdrawal sleeves during manufacture Figures 2a - 2d show finished withdrawal sleeve and details Figures 3a - 3c show withdrawal sleeve in use

FIGURE DESCRIPTION

Figures 1a to 1d show different steps in the manufacture of a withdrawal sleeve according to the invention. The sleeve 100 is machined from sheet metal 1001 . FIG. 1a schematically shows a piece of sheet metal 1001 in raw form. In FIG. 1b, the edges 1002 are machined out of the metal sheet by means of laser processing, in which short slits are cut into the metal sheet. In this case, the edge radii of the edges 1002 can be produced in an optimized manner on the basis of the selected laser method and the laser parameters used. Ideally, the radius of the engagement edge 101a (see Figures 2b and 2d) is between -0.01 and +0.05 mm, especially between +0.00 and +0.02 mm. It is important to mention here that only parts of the engagement elements can also be machined out of the sheet metal using laser processes, as shown in FIG. 1b.

FIG. 1c shows the sheet metal after one or more further punching steps. The full stamped engagement features 1003 can now be seen, with area around the edges 1002 stamped away in these steps. The edges 1002 were not changed in the process. Further stamped elements 1004 are shown.

FIG. 1d shows the finished withdrawal sleeve 100 after the individual sleeves have been eyed out of the metal sheet and bent. The engagement elements 1003 have been converted into the finished engagement elements 101 and have been bent into the interior of the withdrawal sleeve 100 . The lateral surface 102 forms an outer surface of the withdrawal sleeve 100.

Figures 2a to 2d show the finished withdrawal sleeve 100 and details thereof. FIG. 2a shows a perspective view of the withdrawal sleeve 100 with the outer surface 102 (lateral surface). The engagement elements 101, which are bent into the interior of the sleeve 100, are also clearly visible in this illustration. FIG. 2b shows a plan view of the withdrawal sleeve 100, the lower right area of the withdrawal sleeve being cut away in order to show details of an engagement element 101 (see also the enlargement in FIG. 2d). The engagement edge 101a can now be seen here, which was worked out during production using a laser process (cf. the description of FIGS. 1a to 1d with the radii mentioned). FIG. 2c shows the section B-B (see FIG. 2b), the engaging elements 101 with the edges 101a being clearly visible here.

Figures 3a to 3c show a possible application of the withdrawal sleeve 101 in an exemplary injection device. In this example, the injection device shown is an autoinjector 1. For more details on autoinjectors, reference is made to applications WO 2014146210 A1, WO 2015113172 A1, WO 2016205961 A1, WO 2016205962 A1, WO 2016205963 A1 and WO 2020164910 A1 of the applicant, which are hereby incorporated herein by reference in their entirety. The auto-injector 1 can in particular be a Ypsomate auto-injector from the company Ypsomed (ie the applicant). A pre-filled syringe 2 with an injection needle 3 is arranged in the auto-injector. The medicament present in the pre-filled syringe 2 (not shown) can be administered through the injection needle via an existing drive unit (not shown), for example a combination of a piston rod and a spring. For possible details, reference is again made to the documents cited and incorporated by reference.

FIG. 3b shows a longitudinal section through the front (distal) area of the autoinjector 1. In the stored state, as shown in FIG. 3b, the injection needle 3 is protected by a needle protective cap 4.

At its distal end, the auto-injector includes a needle guard pull-off cap 5. The pull-off sleeve 100 (possibly movable to a certain extent, but not detachable) is arranged therein, see FIGS. 3b and 3c. In this example, the needle guard pull-off cap comprises not only the pull-off sleeve 100 but also the housing 6--as shown. The withdrawal sleeve 100 can be mounted in a fixed or movable manner on the inner region 6a of the housing 6 .

If the auto-injector is to be used for an injection of medication from the pre-filled syringe 2 , the protective needle cap 5 is removed from the auto-injector 1 . Here, the withdrawal sleeve 100 is also withdrawn. The engaging edges 101a of the engaging elements 101 engage in an outer surface of the needle protective cap 4 and also take the needle protective cap with them. Due to the sharp edges 101a produced by laser processes, the edges 101a do not slide off the surface of the needle protective cap but take it with them. A certain and small relative movement between the edges 101a and the outer surface is possible until the engagement edges 101a engage in the outer surface of the needle protective cap.

Obvious variations and modifications to the examples described will be apparent to those skilled in the art after studying the present document, without departing from the inventive idea.

REFERENCE LIST

1 injection device/autoinj ector 2 prefilled syringe/reservoir 3 injection needle 4 needle protective cap 5 needle protective detachable cap 6 housing needle protective detachable cap 6a inner area of the housing 100 withdrawal sleeve 101 engagement elements (in the finished state) 101a engagement edge (in the finished state of the withdrawal sleeve 100) 102 lateral surface 1001 sheet metal 1002 laser-processed edges of the engaging elements 1003 engaging elements after punching 1004 further punched shapes

Claims (6)

Claims 1. Injection device for administering a fluid medicament comprising a housing having a proximal end and a distal end, a medication container that is at least partially mounted in the housing, in particular a prefilled syringe, the medication container comprising a distally arranged opening, an injection needle or cannula which is in fluid communication with the opening and through which the medication can be administered, a protective needle cap which is slipped over the injection needle or cannula and is releasably attached to the medication container at its proximal end, a needle guard pull-off cap, which is detachably arranged at the distal end of the housing, at least encompassing the needle guard pull-off cap a withdrawal sleeve, the withdrawal sleeve comprising engagement elements which act on the needle protective cap when the needle protective removable cap is removed from the housing and remove the needle protective cap from the medicament container, characterized in that the withdrawal sleeve is a stamped and bent part made of sheet metal, in which the engagement elements are at least partially worked out of the sheet metal by means of a laser. 2. Injection device according to the preceding claim, wherein the needle protective pull-off cap further comprises a pull-off cap housing in which the pull-off sleeve is arranged in a fixed or movable but non-detachable manner. 3. Injection device according to the preceding claim, wherein the engagement elements are tab-shaped or tongue-shaped, protrude into the withdrawal sleeve, and the needle guard sleeve can be engaged via the respective free end of the engagement elements. 4. Injection device according to claim 3, wherein the end of the engagement elements opposite the free end merges seamlessly into the withdrawal sleeve and lateral boundaries of the engagement elements run approximately parallel between the free end and the opposite end and the free end of the engagement elements approximately perpendicular to the parallel running lateral boundaries. 5. The injection device as claimed in claim 3, wherein the free ends of the engagement elements have edges which act on the needle protective cap and which have an edge radius of -0.01 mm to +0.05 mm, preferably an edge radius of +0.00 to +0.02 mm 6. A method for producing a withdrawal sleeve for an injection device according to any one of the preceding claims, wherein the method comprises at least the following steps: - Cutting out parts of or whole tab- or tongue-shaped engagement elements by means of laser cutting from a sheet metal strip, - Stamping and bending of the withdrawal sleeve from the laser-processed sheet metal strip, with the engagement elements being bent and protruding into the inside of the sleeve after the stamping and bending process.