CAP ASSEMBLY WITH CARTRIDGE

Abstract

A cap assembly adapted to be attached to a drug delivery device main unit, comprising a drug-filled cartridge with an axially moveable piston and a distal portion with a needle penetratable seal, a needle assembly and a cap. The needle assembly comprises a needle having a distal skin-piercing end and a proximal seal-piercing end. The cap comprises a reservoir adapted to receive the needle distal end, the cap accommodating the needle assembly and at least the distal portion of the cartridge. The needle assembly and the cartridge are arranged axially moveable relative to each other between an initial state in which the proximal needle end is arranged distally of the cartridge seal, and an operational state in which the proximal needle end has penetrated the cartridge seal, wherein the reservoir is adapted to receive drug from the cartridge via the needle.

Claims

1. A cap assembly adapted to be attached to a drug delivery main unit, comprising: a cartridge filled with a drug and defining a general axis, the cartridge comprising an axially moveable piston and a distal portion with a needle penetrable seal, a needle assembly comprising a hollow needle having a distal skin-piercing needle end and a proximal seal-piercing needle end, a cap comprising a reservoir adapted to receive the needle distal end, the cap accommodating the needle assembly and at least the distal portion of the cartridge, wherein the needle assembly and the cartridge are arranged axially moveable relative to each other between an initial state in which the proximal needle end is arranged distally of the cartridge seal, and an operational state in which the proximal needle end has penetrated the cartridge seal, and wherein the reservoir is adapted to receive drug from the cartridge via the hollow needle.

2. The cap assembly as in claim 1, in combination with a drug delivery main unit comprising: a housing, a piston rod, and a dose setting and expelling mechanism adapted to move the piston rod distally corresponding to a set dose, wherein the cartridge and the drug delivery main unit are adapted to be releasably connected to each other, the piston rod being arranged to engage and move the cartridge piston distally to thereby expel an amount of drug from the cartridge via the hollow needle, the cap being releasably mounted relative to the cartridge.

3. The cap assembly in combination with the drug delivery main unit as in claim 2, wherein the cartridge is arranged to be moved distally into engagement with the needle assembly corresponding to the operational state when the cap assembly in the initial state and the drug delivery main unit are connected to each other.

4. The cap assembly as in claim 1, further comprising a cartridge unit, the cartridge unit comprising: the cartridge, cartridge unit first coupling structure, cartridge unit second coupling structure, and cartridge unit guide structure, the cap further comprising cap guide structure adapted to engage the cartridge unit guide structure to provide guided axial movement there between, wherein the needle assembly comprises needle coupling structure adapted to engage the cartridge unit first coupling structure corresponding to the operational state in which the proximal needle end has penetrated the cartridge seal, and wherein the cartridge unit can be moved axially from an initial proximal position in which the proximal needle end is arranged distally of the cartridge seal, to a distal operational position in which the proximal needle end has penetrated the cartridge seal and the needle coupling structure has engaged the cartridge unit first coupling structure.

5. The cap assembly as in claim 4, wherein the needle assembly has an initial axial position in which the distal needle end is arranged in the reservoir.

6. The cap assembly as in claim 4, wherein: the needle assembly is arranged axially moveable relative to the cap between an initial position in which the distal needle end is arranged proximally of the reservoir, and an operational position in which the distal needle end is arranged in the reservoir, and the needle assembly is moved from the initial position to the operational position when the cartridge unit is moved from the initial position to the operational position.

7. The cap assembly as in claim 4, in combination with a drug delivery main unit comprising: a housing, a piston rod, a dose setting and expelling mechanism adapted to move the piston rod distally corresponding to a set dose, and main unit coupling structure, wherein the cap assembly and the drug delivery main unit are adapted to be releasably connected to each other, the piston rod being arranged to engage and move distally the cartridge piston to thereby expel an amount of drug from the cartridge via the hollow needle, and wherein the main unit coupling structure is adapted to releasably engage the cartridge unit second coupling structure.

8. The cap assembly in combination with a drug delivery main unit as in claim 7, wherein the cartridge unit is arranged to be moved distally into the distal operational position in which the proximal needle end has penetrated the cartridge seal and the needle coupling structure has engaged the cartridge unit first coupling structure when the cap assembly is connected to the drug delivery main unit.

9. The cap assembly in combination with a drug delivery main unit as in claim 7, wherein the cartridge unit further comprises third coupling structure, and the cap further comprising cap coupling structure adapted to releasably engage the cartridge unit third coupling structure.

10. The cap assembly in combination with a drug delivery main unit as in claim 2, wherein: the piston rod can be arranged in a proximal-most initial position, the piston in a fully filled cartridge axially is arranged within an initial pre-defined positional range, and the cartridge is axially moveable relative to the cap from an initial to an operational position, wherein the cap assembly with the cartridge in the initial positon can be connected to the drug delivery main unit from: (i) an initial axial position in which the piston rod engages the cartridge piston, via (ii) an intermediate axial position in which the cartridge has been moved to a distal-most position in the cap and into engagement with the needle assembly, the proximal needle end thereby penetrating the cartridge seal, and to (iii) an operational axial position in which the cartridge piston has been moved distally in the cartridge to thereby expel an amount of drug into the reservoir via the hollow needle.

11. The cap assembly in combination with a drug delivery main unit as in claim 2, wherein the drug delivery main unit further comprises dose capture circuitry adapted to determine variation of a parameter in the cap assembly or the drug delivery main unit being indicative of the size of a set and/or an expelled amount of drug.

12. The cap assembly in combination with a drug delivery main unit as in claim 11, wherein the detected parameter is rotation of a component in the dose setting and expelling mechanism.

13. The cap assembly in combination with a drug delivery main unit as in claim 11, further comprising wireless communication structure allowing captured data to be transmitted to an external device.

14. The cap assembly as in claim 1, wherein the reservoir is in the form of a sealed chamber with a needle penetratable barrier adapted to receive the distal needle end.

15. The drug delivery assembly as in claim 14, wherein the sealed chamber is vented to the interior of the cap.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In the following the invention will be further described with reference to the drawings, wherein

[0049] FIG. 1 shows a drug delivery device main unit with a mounted cartridge unit,

[0050] FIG. 2 shows the drug delivery device main unit of FIG. 1 detached from the cartridge unit,

[0051] FIG. 3 shows a cartridge unit in a partial see-through representation, the cartridge being in a proximal position,

[0052] FIG. 4A shows the cartridge unit of FIG. 3 in a partial cross-sectional representation, the cartridge being in a distal position,

[0053] FIG. 4B shows the cartridge unit of FIG. 4A in a cross-sectional representation,

[0054] FIG. 5 shows the drug delivery device main unit of FIG. 1 in a cross-sectional view,

[0055] FIGS. 6A-6E show in cross-section and in different states the cartridge unit being mounted on the drug delivery device main unit, and

[0056] FIG. 7 shows in cross-section the cartridge unit fully mounted on the drug delivery device main unit with the cap member being removed.

[0057] In the figures like structures are mainly identified by like reference numerals.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0058] When in the following terms such as upper and lower, right and left, horizontal and vertical or similar relative expressions are used, these only refer to the appended figures and not necessarily to an actual situation of use. The shown figures are schematic representations for which reason the configuration of the different structures as well as their relative dimensions are intended to serve illustrative purposes only. When the term member or element is used for a given component it generally indicates that in the described embodiment the component is a unitary component, however, the same member or element may alternatively comprise a number of sub-components just as two or more of the described components could be provided as unitary components, e.g. manufactured as a single injection moulded part. When it is defined that members are mounted axially free to each other it generally indicates that they can be moved relative to each other, e.g. between defined stop positions whereas when it is defined that members are mounted rotationally free to each other it generally indicates that they can be rotated relative to each other either freely or between defined stop positions. The terms assembly and subassembly do not imply that the described components necessarily can be assembled to provide a unitary or functional assembly or subassembly during a given assembly procedure but is merely used to describe components grouped together as being functionally more closely related.

[0059] Referring to FIGS. 1 and 2 a pen-formed drug delivery device 1 will be described. More specifically, the pen device 1 is in the form of an assembly comprising a drug delivery main unit 100 which in the shown operational state in FIG. 1 is releasably coupled to a cartridge unit 200. FIG. 2 shows the cartridge unit removed from the main unit.

[0060] The cartridge unit 200 comprises a generally tubular cartridge holder 210 in which a drug-filled transparent cartridge 220 is arranged, the cartridge comprising a proximally facing and axially moveable piston and a distal portion with a needle penetratable septum. The cartridge may for example contain an insulin, a GLP-1 or a growth hormone formulation. A pair of opposed openings 211 formed in the cartridge holder allows the cartridge and its content to be inspected by a user. The cartridge unit further comprises a needle assembly 230 comprising a hollow needle having a distal skin-piercing needle portion 231 and a proximal septum-piercing needle portion 232 which in the shown state is arranged in fluid communication with the cartridge interior.

[0061] The drug delivery main unit 100 comprises a proximal body portion 110 and a distally extending guide portion 120. A dose setting and expelling mechanism is arranged in the proximal body portion and comprises a piston rod adapted to engage the cartridge piston of a mounted cartridge unit to thereby expel a dose of drug via the hollow needle as it is moved distally. A proximal rotatable dose setting member 180 serves to manually set a desired dose of drug shown in a display window 112 and which can then be expelled when the release button 190 is actuated. The window is in the form of an opening in the housing allowing a portion of a helically rotatable indicator member (scale drum) 170 to be observed. Depending on the type of expelling mechanism embodied in the drug delivery device, the expelling mechanism may comprise a spring as in the shown embodiment which is strained during dose setting and then released to drive the piston rod when the release button is actuated. Alternatively the expelling mechanism may be fully manual in which case the dose member and the actuation button moves proximally during dose setting corresponding to the set dose size, and then is moved distally by the user to expel the set dose.

[0062] The distally extending guide portion 120 comprises guide means 128 adapted to engage corresponding guide means 218 arranged on the cartridge holder, the guide means allowing the cartridge unit to be mounted in an axial direction in sliding engagement with the guide portion of the device main unit. FIG. 1 shows the cartridge unit 200 being fully mounted in a proximal-most position relative to the main unit 100, the two units being releasably coupled to each other by corresponding releasable coupling means. The coupling means may be formed as part of the guide means 128, 218. Alternatively the coupling means may be arranged on the main unit body portion and the corresponding portion on the cartridge unit.

[0063] The drug delivery device further comprises a cap member (see below) adapted to cover the cartridge unit (and in the shown embodiment also the guide portion) when mounted. As will be described in greater detail below, the cap in the shown embodiment comprises a reservoir in the form of a sealed chamber adapted to receive an amount of preservative-containing drug from the cartridge.

[0064] The shown drug delivery device 1 may be provided with electronic circuitry comprising sensor means adapted to detect a property related to the size of a set and/or expelled dose amount of drug, e.g. the amount of rotation of an indicator member during dose expelling. The electronic circuitry may be provided with display means allowing determined dose sizes to be displayed and/or communication means allowing dose related data to be transmitted to an external device, e.g. wirelessly to a smartphone for subsequent analysis and display.

[0065] With reference to FIGS. 3, 4A and 4B the cartridge unit 200 will be described in greater detail.

[0066] Referring first to FIG. 3 the cartridge holder 210 and the needle assembly 230 is shown in their initial before-use position inside cap member 240, the latter represented by an exterior outline but without any interior details. In the following the combined cap and cartridge unit assembly will be denoted cap assembly 201. A drug-filled cartridge 220 with an axially displaceable piston 221 and a distal needle-penetratable septum 222 is arranged axially locked inside the cartridge holder. The cartridge comprises a reduced-diameter distal portion 223 providing a circumferential coupling space between the cartridge distal portion and the cartridge holder distal portion. The cartridge holder is coupled non-rotationally but axially moveable to the cap, and is moveable in a distal direction between an initial proximal position as shown in FIG. 3 and an operational distal position as shown in FIGS. 4A and 4B. In the shown embodiment the cartridge holder is coupled to the cap by means of two pairs of opposed protrusions 215, 216 engaging corresponding slots 242 in the cap, the coupling (or guide) subsequently allowing the cap to be removed from and remounted on the cartridge holder. Between the cartridge holder and the cap a releasable axial lock is provided to properly secure the cartridge holder in the initial position prior to use, e.g. by means of protrusions 243 in the guiding slots adapted to cooperate with the protrusions 216 on the cartridge holder, the lock being designed to be overcome by an axial force applied to the cartridge holder.

[0067] Along the length of the cartridge holder a longitudinal space 249 is formed between the cartridge holder and the cap inner surface, the space being adapted to receive and accommodate the above-described main unit guide portion.

[0068] The needle assembly 230 comprises a hub member 235 in which the hollow needle with its distal skin-piercing needle portion 231 and proximal septum-piercing needle portion 232 is mounted, the hub member being releasably mounted in a parked position by gripping means 241 formed in the cap member, the parked position corresponding to both an initial before-use position and the position during use with the cap mounted. The hub member comprises a proximally facing circumferential skirt portion 236 adapted to be received in the coupling space (as shown in FIGS. 4A and 4B), the skirt portion comprising coupling means 237 adapted to engage corresponding coupling means on the cartridge and/or cartridge holder. In the shown embodiment the coupling means is in the form of a threaded outer surface 227 formed on a generally tubular coupling member 226 mounted on the cartridge distal portion 223, and a number of flexible gripping ribs 237 formed on the skirt inner surface, the coupling arrangement allowing the skirt portion to axially engage the threaded surface, yet allows the needle assembly to be removed by rotation if deemed necessary, e.g. in order to allow a damaged needle to be replaced. Alternatively the coupling may be non-releasable.

[0069] The cap is further provided with a sealed chamber 245 comprising first and second openings. The first opening is sealed with a needle-penetratable septum 246 and the second opening is in the form of a tubular bore 247 in which a plug 248 formed from a flexible material is arranged, the plug serving as a seal as well as a pressure/overflow relief valve in communication with the interior of the cap. With the needle assembly 230 in its parked position the distal needle portion 231 is arranged in the sealed chamber 245 penetrating the septum 246. In the initial state the shown sealed chamber is empty, however, as will be explained below the chamber is adapted to receive and hold an amount of preservative-containing drug from the cartridge, the preservatives ensuring a sterile or near-sterile environment for the needle distal portion in the parked position, this allowing the needle to be re-used corresponding to the intended use-time for the cartridge unit. Indeed, prior to use the cartridge unit will have to be designed and packaged in such a way that sterility of both the proximal and distal ends of the needle is safeguarded.

[0070] FIG. 5 shows in cross-section a schematic representation of the drug delivery main unit 100 comprising a dose setting and expelling mechanism 130, electronic circuitry 140 arranged in the guide portion as well as an energy source, e.g. a replaceable or non-replaceable AAA or AAAA battery 145 as shown in case the main unit is of the durable type. The dose setting and expelling mechanism is only shown schematically comprising a threaded piston rod 131 having a distal piston-engaging foot portion 132, a driver 133 for rotating the piston rod, a scale drum 134, a drive spring (not shown), a dose setting member 180, a release member 190 and a coupling mechanism 135 allowing the piston rod to be returned to an initial proximal position during exchange of a cartridge unit. Alternatively the foot portion may be in the form of a piston washer connected to the piston rod to allow the washer to wobble. The dose setting and expelling mechanism may be of any suitable design, e.g. utilizing the design and concepts described in EP 17151586.9. Correspondingly, the electronic circuitry and the associated sensor means may be of any suitable design allowing a relevant dose related property to be determined, e.g. a rotary sensor assembly of the type described in EP 17151586.9 or a magnet-based system as described in WO 2014/161952.

[0071] With reference to FIGS. 6A-6E the mounting of a cap assembly and thereby a cartridge unit on the drug delivery main unit will be described. The cap assembly 201 and the cartridge unit 200 correspond to the cap and cartridge units described with reference to FIGS. 3, 4A and 4B, and the main unit 100 corresponds to the main unit described with reference to FIG. 5.

[0072] FIG. 6A shows the cap assembly 201 and main unit 100 separated from each other, the piston rod 131 in the main unit being positioned in its proximal-most position. The cap assembly 201 is in an initial state with the cartridge holder 210 in a proximal position and the drug-filled cartridge 220 thus not yet in flow communication with the hollow needle 232. In FIG. 6B the guide and coupling means 128 on the main unit distal guide portion has been mated with the corresponding guide and coupling means 218 on the cartridge holder, this allowing the guide portion 120 to be introduced into the receiving space 249 in the cap. In FIG. 6C the guide portion 120 has been inserted further into the cap 240 to the position in which the piston rod distal end 132 just engages the free end of the cartridge piston 221. At this point the user will feel a resistance to further insertion of the guide portion due to the axial lock between the cartridge holder 210 and the cap member 240.

[0073] When the resistance is overcome and the axial lock released the engagement with the piston rod 131 will prevent the sealed drug-filled cartridge 220 and thus the cartridge holder 210 from being moved further proximally relative to the main unit 100, this providing that the cap 240 with the cap-mounted needle assembly 230 is moved proximally, the skirt portion 235 thereby being inserted in the circumferential coupling space. As a result the proximal needle portion 232 penetrates the cartridge septum 222 and the skirt portion coupling means 237 engages the corresponding coupling means 227 on the cartridge as shown in FIG. 6D, a flow communication between the cartridge interior and the cap sealed chamber 245 thereby being established. As the cartridge holder 210 has been moved to its distal-most position in the cap member 240 further advancement of the guide portion 120 into the cap results in the cartridge piston 221 being moved distally in the cartridge until the cartridge holder 210 engages the main unit housing 110 as shown in FIG. 6E, whereby an amount of fluid drug is transferred to the cap sealed chamber 245, the amount corresponding to the distance G between the cartridge holder and the main unit housing shown in FIG. 6D. Indeed, for this to happen it is necessary that the cartridge piston 221 initially is positioned within a pre-defined axial positional range, the range ensuring that the sealed chamber 245 as a minimum is filled with the minimally required amount of preservative-containing drug, or as a maximum with an amount of drug resulting in an overflow of an acceptable small amount of drug out into the cap interior. A fluid trap for this purpose may be provided in the cap.

[0074] Although in the above description the distal movement of the cartridge holder and the transfer of drug to the sealed chamber are described as taking part in sequence, a certain overlap in time between the two events may be the case.

[0075] When the cartridge holder engages the main unit, the two units are releasably locked to each other, e.g. by means of a snap coupling. At the same time the piston rod coupling is actuated from a resetting state in which it can be moved to its proximal-most position, to an operational state in which it is coupled to the expelling mechanism for subsequent movement in the distal direction during expelling of a dose of drug from the cartridge. Correspondingly, when a used cartridge unit is released from the main unit the piston rod coupling is actuated to its resetting state allowing the piston rod to be moved proximally, either by hand prior to attaching a new cartridge unit or simply by allowing the new cartridge unit to move the piston rod proximally to its proximally-most position. Indeed, the resistance to axial movement of the piston rod should be sufficiently low to prevent that the cartridge is released from its locked position in the cap. To further simplify removal of a used cartridge unit from the main unit, the cap may be designed to allow the snap lock to be released without the cap member having to be removed.

[0076] As appears, by the above arrangement a semi-disposable drug delivery system is provided which offers a very high degree of simplicity and user-friendliness, as a new cartridge unit can be mounted and primed and be ready for use virtually in a few seconds. Correspondingly, when a dose has been set the user can remove the cap and immediately use the device to dispense the set dose without having to bother with the mounting of a new needle assembly, see FIG. 7. Indeed, the dose can also be set after the cap has been removed.

[0077] Further, in the shown embodiment a relative large replaceable battery has been incorporated, this allowing high-power wireless communication to be implemented, e.g. providing safe and reliable communication with e.g. a smartphone carried by the user without having to position the two devices in the vicinity of each other.

[0078] In the above description of exemplary embodiments, the different structures and means providing the described functionality for the different components have been described to a degree to which the concept of the present invention will be apparent to the skilled reader. The detailed construction and specification for the different components are considered the object of a normal design procedure performed by the skilled person along the lines set out in the present specification.