Cap for a drug delivery device and method for manufacturing a cap for a drug delivery device

This disclosure relates to a cap for a drug delivery device and to a method for manufacturing a cap for a drug delivery device. A drug delivery device may have a cap which is releasably attachable to a dispensing end of the drug delivery device. A needle assembly located at the dispensing end of the device may be protected by means of the cap.

A drug delivery device is described in document EP 1 923 083 A1 , for example.

It is an object of the present disclosure to facilitate provision of a novel, preferably an improved, drug delivery device, for example a device providing high safety for a user.

This object may be achieved by the subject matter of the independent claims. Further features and advantageous embodiments are the subject matter of the dependent claims.

According to one aspect a cap for a drug delivery device is provided. The cap may comprise at least one window section. The window section may be configured for displaying information through a wall of the cap. The cap may comprise a non-window section. The window section may be a solid window section of the cap. The non-window section may be a solid non-window section of the cap. Thus, both sections, the window section and the non-window section, may be solid sections. The cap may be securable against axial and rotational movement with respect to the device. The solid window section may be adapted to enable information located underneath the window section to be viewed by a user when the cap is attached to the device. The solid window section may protect parts of the device located underneath the window section from external influences. The solid non-window section may protect parts of the device located underneath the non-window section from external influences. A further aspect relates to a drug delivery device. The drug delivery device may comprise the previously mentioned cap. The cap may be a unitary component.

Alternatively, the cap may be a multi-piece component, e.g. a two-piece component, comprising a solid cap part having an aperture and a solid transparent window insert. The window insert may be secured to the cap part and may extend over the aperture. The drug delivery device may comprise a needle. The needle is expediently, preferably permanently or detachably, mounted to a dispensing end of the device. The cap may be suitable to cover the dispensing end of the drug delivery device. The cap may comprise an opening. The dispensing end of the drug delivery device may be guidable through the opening for attaching the cap to the device, for example by a snap-fit connection. The axial position of the window section may be configured such that the needle could pierce from inside the cap through the window section to the outside of the cap.

Additionally or alternatively, the length of the needle may be configured such that the needle could pierce from inside the cap through the window section to the outside of the cap. Additionally or alternatively, the radial extension of the opening may be configured such that the needle could pierce from inside the cap through the window section to the outside of the cap. Additionally or alternatively, the radial extension of a section of the device being arranged adjacent to the dispensing end of the device may be configured such that the needle could pierce from inside the cap through the window section to the outside of the cap. The solid window section may be adapted and arranged to prevent the needle from piercing through the window section from inside the cap to the outside of the cap when the cap is attached to the device.

The window section may comprise a thickness which is adapted to prevent the needle from piercing through the window section when the cap is attached to the device.

Additionally, the non-window section may comprise a thickness which is adapted to prevent the needle from piercing through the non-window section when the cap is attached to the device. According to an embodiment, the thickness of the window section and/or the non- window section is greater than or equal to 0.7 mm.

The thickness of the window section and/or the non-window section may be such that a needle comprising a needle gauge equal to or greater than G30 may be prevented from piercing through the window section and/or the non-window section when the cap is attached to the device. In particular, for the window section and/or the non-window section comprising a wall thickness equal to 0.7 mm, for example, a needle comprising a needle gauge of G30 or G32 may be prevented from piercing through the window section and/or the non-window section when the cap is attached to the device. User injuries, caused by the needle protruding through the window section and/or the non- window section may be prevented in this way. Hence, provision of a safely operable drug delivery device is facilitated. A further aspect relates to a method for manufacturing a cap for a drug delivery device. Therein, a solid cap part may be formed. Furthermore, at least one solid window section may be defined in the cap part. Accordingly, a cap may be formed comprising the solid window section and a solid non-window section. The cap may enable quick retrieval of important information by means of the window section when the cap is attached to the device.

According to an embodiment, the window section is transparent. The non-window section may be less transparent than the window section.

The transparent window section enables retrieval of information located underneath the window section. Information located underneath the non-window section may be suppressed by the less transparent non-window section. According to an embodiment, the drug delivery device comprises a cartridge holder. The cartridge holder may be adapted to retain a cartridge. The cartridge may contain a drug. The window section may be adapted and arranged to display information revealed by at least one of the cartridge holder and the cartridge.

The cap may be adapted to cover the dispensing end of the device including the needle assembly and at least a part of the cartridge holder. The respective window section may be expediently configured to display information revealed by at least one of cartridge holder and the cartridge when the cap is attached to the device.

According to an embodiment, the cap is a unitary component.

The cap may be a single injection moulded piece, for example. In this way, a small number of steps is needed for manufacturing the cap and, hence, manufacturing costs may be reduced. According to an embodiment, the method for manufacturing the cap comprises the step of forming the cap part by injection moulding using a first material. In a next step, the window section may be defined by injection moulding using a second material. The first material may be less transparent than the second material. The cap part and the window section may be formed together in a single injection moulding process.

Accordingly, provision of a unitary cap may be facilitated. Manufacturing costs may be reduced in this way.

According to an embodiment, the cap part is transparent. One of the window section and the non-window section may be defined by freezing a section of the transparent cap part. The other one of the window section and the non-window section may be defined by a non-frozen section of the transparent cap part.

Accordingly, provision of a unitary cap may be facilitated. The cap, in particular the cap part, may be formed in an injection moulding process using one single transparent material, for example. Freezing of a section of the cap part may allow for a flexible definition of the window section, in particular of the shape of the window section. The window section may be elongated. A plurality of window sections may be defined by freezing predetermined sections of the cap part.

According to an embodiment, the method for manufacturing the cap comprises the step of forming the cap part. The cap part may be solid. The cap part may be formed from injection moulding, for example. The cap part may have at least one aperture. In a next step, at least one solid window insert may be formed. The window insert may be formed from injection moulding, for example. In a further step, the window insert may be inserted in the window aperture. The window insert may be inserted in the window aperture such that the window aperture is closed by means of the window insert. In a next step, the window insert may be secured, preferably permanently or releasably secured, to the cap part. The window insert may be secured to the cap part, for example by means of a snap-fit connection, to form the cap. Accordingly, the cap may comprise a two-piece component. The cap may comprise the solid cap part and the solid window insert. The solid window insert may be adapted to prevent the needle from piercing through the window section when the cap is attached to the device. The window insert may be exchangeable. According to an embodiment, the window insert is transparent. The cap part may be less transparent than the window insert.

Information located underneath the aperture may be visible through the transparent window insert. Piercing of the needle through the window section from inside the cap to the outside of the cap may be prevented by means of the solid material of the window insert.

According to a preferred embodiment, a cap for a drug delivery device is provided, the cap comprising at least one window section for displaying information through a wall of the cap and a non-window section. The window section is a solid window section of the cap. The non-window section is a solid non-window section of the cap. User-relevant information, e.g. the kind of a drug contained in a cartridge of the device, may be effectively displayed by means of the window section when the cap is attached to the device. Additional information, which may confuse the user, located underneath the non-window section may be effectively suppressed. The solid material may prevent a needle, attached to a dispensing end of the device, from piercing through the window section and/or the non-window section. User injuries caused by the needle piercing through the window section and/or the non-window section may be prevented in this way. According to a further preferred embodiment, a method for manufacturing a cap for a drug delivery device is provided comprising the steps of forming a solid cap part and defining at least one solid window section in the cap part to form a cap comprising a solid window section and a solid non-window section. The cap facilitates provision of a device with high user safety. User injuries, e.g.

needleprick injuries, may be prevented by means of the solid window section and/or the solid non-window section which prevent a needle attached to the dispensing end of the device from piercing through the window section and/or the non-window section when the cap is attached to the device. User-relevant information can be retrieved quickly via the window section when the cap is attached to the device. Confusing information may be suppressed by means of the non-window section.

Of course, features described above in connection with different aspects and

embodiments may be combined with each other and with features described below.

Further features and refinements become apparent from the following description of the exemplary embodiments in connection with the accompanying figures.

Figure 1 schematically shows a perspective side view of an exemplary embodiment of a drug delivery device,

Figure 2 schematically shows a part of the drug delivery device of Figure 1 . Like elements, elements of the same kind and identically acting elements may be provided with the same reference numerals in the figures. In Figure 1 an exemplary embodiment of a drug delivery device 1 is shown. The drug delivery device comprises a housing 2. The drug delivery device 1 and the housing 2 have a distal end and a proximal end. The term "distal end" designates that end of the drug delivery device 1 or a component thereof which is or is to be arranged closest to a dispensing end of the drug delivery device 1 . The distal end of the device 1 is indicated by arrow 10. The term "proximal end" designates that end of the device 1 or a component thereof which is or is to be arranged furthest away from the dispensing end of the device 1 . The proximal end of the device 1 is indicated by arrow 1 1 . The distal end and the proximal end are spaced apart from one another in the direction of an axis. The axis may be the main longitudinal axis 20 of the device 1 .

The drug delivery device 1 comprises a cartridge holder 3. The cartridge holder 3 is secured to the housing 2. The device 1 comprises a cartridge 4. The cartridge 4 is retained in the cartridge holder 3. The cartridge holder 3 stabilizes the cartridge 4 mechanically. The proximal end of the cartridge 4 is indicated by a dashed-dotted line.

The cartridge 4 may hold a plurality of doses of a drug 18. The drug 18 is preferably a liquid medication, comprising, for example, insulin, like short-acting or long-acting insulin, heparin and/or growth hormones. The term "drug", as used herein, preferably means a pharmaceutical formulation containing at least one pharmaceutically active compound, wherein in one embodiment the pharmaceutically active compound has a molecular weight up to 1500 Da and/or is a peptide, a proteine, a polysaccharide, a vaccine, a DNA, a RNA, an enzyme, an antibody, a hormone or an oligonucleotide, or a mixture of the above-mentioned pharmaceutically active compound, wherein in a further embodiment the pharmaceutically active compound is useful for the treatment and/or prophylaxis of diabetes mellitus or complications associated with diabetes mellitus such as diabetic retinopathy, thromboembolism disorders such as deep vein or pulmonary thromboembolism, acute coronary syndrome (ACS), angina, myocardial infarction, cancer, macular degeneration, inflammation, hay fever,

atherosclerosis and/or rheumatoid arthritis, wherein in a further embodiment the pharmaceutically active compound comprises at least one peptide for the treatment and/or prophylaxis of diabetes mellitus or

complications associated with diabetes mellitus such as diabetic retinopathy, wherein in a further embodiment the pharmaceutically active compound comprises at least one human insulin or a human insulin analogue or derivative, glucagon-like peptide (GLP-1 ) or an analogue or derivative thereof, or exedin-3 or exedin-4 or an analogue or derivative of exedin-3 or exedin-4.

Insulin analogues are for example Gly(A21 ), Arg(B31 ), Arg(B32) human insulin; Lys(B3), Glu(B29) human insulin; Lys(B28), Pro(B29) human insulin; Asp(B28) human insulin; human insulin, wherein proline in position B28 is replaced by Asp, Lys, Leu, Val or Ala and wherein in position B29 Lys may be replaced by Pro; Ala(B26) human insulin;

Des(B28-B30) human insulin; Des(B27) human insulin and Des(B30) human insulin.

Insulin derivates are for example B29-N-myristoyl-des(B30) human insulin; B29-N- palmitoyl-des(B30) human insulin; B29-N-myristoyl human insulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29 human insulin; B28-N-palmitoyl-

LysB28ProB29 human insulin; B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N- palmitoyl- ThrB29LysB30 human insulin; B29-N-(N-palmitoyl-Y-glutamyl)-des(B30) human insulin; B29-N-(N-lithocholyl-Y-glutamyl)-des(B30) human insulin; Β29-Ν-(ω- carboxyheptadecanoyl)-des(B30) human insulin and B29-N-( -carboxyheptadecanoyl) human insulin. Exendin-4 for example means Exendin-4(1 -39), a peptide of the sequence H-His-Gly-

Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-G lu-Ala-Val-Arg-Leu-Phe- lle-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro- Pro-Ser-NH2. Exendin-4 derivatives are for example selected from the following list of compounds:

H-(Lys)4-des Pro36, des Pro37 Exendin-4(1 -39)-NH2,

H-(Lys)5-des Pro36, des Pro37 Exendin-4(1 -39)-NH2,

des Pro36 [Asp28] Exendin-4(1 -39),

des Pro36 [lsoAsp28] Exendin-4(1 -39),

des Pro36 [Met(0)14, Asp28] Exendin-4(1 -39),

des Pro36 [Met(0)14, lsoAsp28] Exendin-4(1 -39),

des Pro36 [Trp(02)25, Asp28] Exendin-4(1 -39),

des Pro36 [Trp(02)25, lsoAsp28] Exendin-4(1 -39),

des Pro36 [Met(0)14 Trp(02)25, Asp28] Exendin-4(1 -39),

des Pro36 [Met(0)14 Trp(02)25, lsoAsp28] Exendin-4(1 -39); or des Pro36 [Asp28] Exendin-4(1 -39),

des Pro36 [lsoAsp28] Exendin-4(1 -39),

des Pro36 [Met(0)14, Asp28] Exendin-4(1 -39),

des Pro36 [Met(0)14, lsoAsp28] Exendin-4(1 -39),

des Pro36 [Trp(02)25, Asp28] Exendin-4(1 -39),

des Pro36 [Trp(02)25, lsoAsp28] Exendin-4(1 -39),

des Pro36 [Met(0)14 Trp(02)25, Asp28] Exendin-4(1 -39),

des Pro36 [Met(0)14 Trp(02)25, lsoAsp28] Exendin-4(1 -39),

wherein the group -Lys6-NH2 may be bound to the C-terminus of the Exendin-4 derivative; or an Exendin-4 derivative of the sequence

H-(Lys)6-des Pro36 [Asp28] Exendin-4(1 -39)-Lys6-NH2,

des Asp28 Pro36, Pro37, Pro38Exendin-4(1 -39)-NH2,

H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1 -39)-NH2, H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1 -39)-NH2,

des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Trp(02)25, Asp28] Exendin-4(1 -39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Trp(02)25] Exendin-4(1 -39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(02)25, Asp28] Exendin-4(1 -39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(02)25, Asp28] Exendin-4(1 -39)-NH2, des Pro36, Pro37, Pro38 [Trp(02)25, Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(02)25, Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(02)25, Asp28] Exendin-4(1 -39)-(Lys)6-NH2, H-(Lys)6-des Pro36 [Met(0)14, Asp28] Exendin-4(1 -39)-Lys6-NH2,

des Met(0)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1 -39)-NH2,

H-(Lys)6-desPro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-NH2, des Pro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-(Lys)6-NH2, H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-(Lys)6-NH2, H-Lys6-des Pro36 [Met(0)14, Trp(02)25, Asp28] Exendin-4(1 -39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Met(0)14, Trp(02)25] Exendin-4(1 -39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(0)14, Asp28] Exendin-4(1 -39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(0)14, Trp(02)25, Asp28] Exendin-4(1 -39)- NH2,

des Pro36, Pro37, Pro38 [Met(0)14, Trp(02)25, Asp28] Exendin-4(1 -39)-(Lys)6-NH2, H-(Lys)6-des Pro36, Pro37, Pro38 [Met(0)14, Trp(02)25, Asp28] Exendin-4(S1 -39)- (Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(0)14, Trp(02)25, Asp28] Exendin-4(1 -39)- (Lys)6-NH2; or a pharmaceutically acceptable salt or solvate of any one of the afore-mentioned Exedin-4 derivative. Hormones are for example hypophysis hormones or hypothalamus hormones or regulatory active peptides and their antagonists as listed in Rote Liste, ed. 2008, Chapter 50, such as Gonadotropine (Follitropin, Lutropin, Choriongonadotropin,

Menotropin), Somatropine (Somatropin), Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin, Buserelin, Nafarelin, Goserelin.

A polysaccharide is for example a glucosaminoglycane, a hyaluronic acid, a heparin, a low molecular weight heparin or an ultra low molecular weight heparin or a derivative thereof, or a sulphated, e.g. a poly-sulphated form of the above-mentioned

polysaccharides, and/or a pharmaceutically acceptable salt thereof. An example of a pharmaceutically acceptable salt of a poly-sulphated low molecular weight heparin is enoxaparin sodium.

Pharmaceutically acceptable salts are for example acid addition salts and basic salts. Acid addition salts are e.g. HCI or HBr salts. Basic salts are e.g. salts having a cation selected from alkali or alkaline, e.g. Na+, or K+, or Ca2+, or an ammonium ion

N+(R1 )(R2)(R3)(R4), wherein R1 to R4 independently of each other mean: hydrogen, an optionally substituted C1 -C6-alkyl group, an optionally substituted C2-C6-alkenyl group, an optionally substituted C6-C10-aryl group, or an optionally substituted C6-C10- heteroaryl group. Further examples of pharmaceutically acceptable salts are described in "Remington's Pharmaceutical Sciences" 17. ed. Alfonso R. Gennaro (Ed.), Mark Publishing Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia of Pharmaceutical Technology. Pharmaceutically acceptable solvates are for example hydrates.

The cartridge 4 has a distally arranged outlet (not explicitly shown). The drug 18 can be dispensed from the cartridge 4 through the outlet. The outlet may be covered by a membrane or septum (not explicitly shown). The membrane may protect the drug 18 against external influences during storage of the cartridge 4. The membrane may seal the outlet fluid-tightly. The drug delivery device 1 may comprise a needle assembly (not explicitly shown), comprising a needle. The needle assembly may be releasably attached to the cartridge holder 3, for example by means of engaging means 5, e.g. a thread. The needle may be in fluid communication with the interior of the cartridge 4.

The drug delivery device 1 comprises a bung 7. The bung 7 is moveably retained in the cartridge 4. The bung 7 seals the cartridge 4 proximally. Movement of the bung 7 in the distal direction with respect to the cartridge 4 causes a dose of the drug 18 to be dispensed from the cartridge 4.

The device 1 comprises a piston rod 6. The device 1 comprises a drive mechanism (not explicitly shown). The drive mechanism is arranged at least partly within the housing 2 of the drug delivery device 1. The drive mechanism comprises a button 8, e.g. a button 8 actuatable for setting and/or injecting the dose. The drive mechanism is configured to drive the piston rod 6 in the distal direction with respect to the cartridge 4. In this way, a dose of the drug 18 is dispensed from the cartridge 4. The size of the dispensed dose is determined by the distance by which the bung 7 is displaced in the distal direction with respect to the cartridge 4. The drug delivery device 1 may be an injection device. The drug delivery device 1 may be a pen-type device, in particular a pen-type injector. The device 1 may be a disposable or a re-usable device. The device 1 may be configured to dispense fixed doses of the drug 18, in particular doses which may not be varied by the user, or variable, preferably user-settable, doses of the drug 18. The drug delivery device 1 may be a manually, in particular a non-electrically, driven device.

The drug delivery device 1 comprises a cap 9. The cap 9 is attachable to the drug delivery device 1. The cartridge holder 3 comprises at least one securing member 12. The cap 9 may be releasably secured, e.g. by a snap-fit connection, to the cartridge holder 3 by means of mechanical cooperation of the securing member 12 and a mating securing member arranged on an inner surface of the cap (not explicitly shown).

Alternatively, the securing member 12 may be provided on the housing 2. The cap 9 may be releasably secured against rotational and axial movement with respect to the housing 2 by means of mechanical cooperation of the securing member 12 and the mating securing member. The cap 9 is configured to cover the distal end, in particular the dispensing end, of the drug delivery device 1 including the previously mentioned needle assembly. The cap 9 is configured to cover at least partly the cartridge holder 3 retaining the cartridge 4.

The cap 9 comprises a non-window section 17. The non-window section 17 may be a solid section of the cap 9. The non-window section 17 may be an opaque section. The cap 9 comprises at least one window section 13. The cap 9 may comprise two window sections 13 (not explicitly shown). The window sections 13 may be arranged oppositely and/or axially offset with respect to each other (not explicitly shown). The respective window section 13 may be a solid section of the cap 9. The window section 13 may be a transparent section.

The cap 9 comprises an opening 16. The opening 16 is adapted and arranged such that the dispensing end of the drug delivery device 1 is guided through the opening 16 for attaching the cap 9 to the device 1 .

The cap 9 and the drug delivery device 1 are configured such that the needle could pierce through the window section 13 of the cap 9 when the cap 9 is attached to the dispensing end of the device 1 . The solid window section 13 is adapted to prevent the needle from piercing through the window section 13 which is described later on in more detail.

The needle could pass from inside the cap 9 through the window section 13 to the outside of the cap 9 due to the arrangement and/or the configuration of parts of the drug delivery device 1 and/or of the cap 9. In particular, one, or two or a plurality of variables may be responsible for the fact that the needle could pass through the window section 13. The variables may comprise the radial extension of the opening 16 with respect to the main longitudinal axis 20. Additionally or alternatively, the variables may comprise the radial extension of a section of the cap 9 which is arranged closer to the distal end of the cap 9 than the opening 16. Additionally or alternatively, the variables may comprise the radial extension with respect to the main longitudinal axis 20 of a section of the device 1 being arranged adjacent to the dispensing end of the device 1 , e.g. a distal section of the cartridge holder 3. Additionally or alternatively, the variables may comprise the axial position and/or the axial extension of the at least one window section 13 with respect to the main longitudinal axis 20. Additionally or alternatively, the variables may comprise the length of the needle.

In particular, when the at least one window section 13 is arranged close to the proximal end of the cap 9, the dispensing end of the device 1 and, hence, the needle may be inserted in an inclined fashion into the opening 16 such that the needle could pierce through the window section 13, in particular through a proximal portion of the window section 13, when attaching the cap 9 to the device 1 . This may especially be the case when the device 1 comprises a long needle.

Additionally or alternatively, when the radial extension of the cartridge holder 3 is smaller than the radial extension of the cap 9 and, in particular of the opening 16, the needle, which was already guided through the opening 16 in an axially aligned fashion, could be put into slope with respect to the main longitudinal axis 20 while attaching the cap 9 to the distal end of the device 1 such that the needle could pass through the window section 13, in particular through a distal section thereof.

The solid window section 13 comprises a thickness which is adapted to prevent the needle from piercing through the window section 13 when the cap 9 is attached to the device 1 . For example, the window section 13 may comprise, at least in parts, a thickness greater than or equal to 0.7 mm.

The solid non-window section 17 may comprise a thickness adapted to prevent the needle from piercing through the non-window section 17 when the cap 9 is attached to the dispensing end of the device 1 . The non-window section 17 may comprise, at least in parts, a thickness greater than or at least equal to 0.7 mm. The thickness may be suited to prevent a needle comprising a needle gauge of G30 or G32, for example, from piercing through the window section 13 and/or the non-window section 17 when the cap 9 is attached to the device 1 . User injuries caused by the needle protruding through the window section 13 and/or the non-window section 17 may be prevented in this way. Hence, provision of a safely operable drug delivery device 1 is facilitated.

Figure 2 schematically shows a part the drug delivery device of Figure 1. In particular, Figure 2 shows the cap 9 of the device 1 .

The respective solid window section 13 comprises a transparent material. The respective transparent solid window section 13 is configured to display information revealed by at least one of the cartridge holder 3 and the cartridge 4 when the cap 9 is attached to the device 1 . For example, the respective window section 13 may be configured to display information about the content of the cartridge 4, e.g. the type of the drug 18 held in the cartridge 4, which information can be revealed on the cartridge holder 3, for example. According to an embodiment, the respective window section 13 is adapted and arranged to display information comprising a fill status of the cartridge 4, for example. When the drug 18 is dispensed from the drug delivery device 1 , the bung 7 progressively moves forward towards the distal end of the cartridge 4. Through the respective window section 13 the position of the bung 7 may be visible for the user. Accordingly, the fill status of the drug delivery device 1 can be recognized by viewing the bung 7 through the window section 13. According to one embodiment, a plurality of symbols 15 is printed onto the respective window section 13. The symbols 15 may be moulded onto the respective window section 13, for example. The symbols 15 may provide information related to a dosage scale. Alternatively, a plurality of symbols 15 may be printed or moulded onto the cartridge holder 3. The symbols 15 may be visible through the transparent window section 13. The symbols 15 may provide a dosage scale retained on the cartridge holder 3. The respective window section 13 is elongated. The window section 13 may be oriented along the main longitudinal axis 20 of the device 1. Alternatively, the respective window section 13 may comprise a circular shape. Alternatively, the respective window section 13 may comprise a square shape. In particular, the shape of the window section 13 may be adapted to the kind of information located underneath the window section 13. An elongated window section 13 may be especially suitable for displaying a row of numbers, e.g. the dosage scale, for example.

The non-window section 17 may be less transparent than the window section 13. The non-window section 17 may be opaque. As the cap 9 is secured against axial and/or rotational movement with respect to the device 1 , information provided axially and/or rotationally offset from the position of the respective window section 13 may be suppressed by means of the non-window section 17. The suppressed information may be present but invisible for the user when the cap 9 covers the distal end of the device 1.

The cap 9 may be a unitary component as mentioned previously. In particular, the respective window section 13 and the non-window section 17 may be formed unitarily.

During manufacture of the cap 9, in a first step, a cap part 19 may be formed. The cap part 19 may be solid. Afterwards, at least one window section 13 may be defined in the cap part 19. The window section 13 may be solid. Accordingly, a cap 9 may be formed comprising a solid window section 13 and a solid non-window section 17. As described previously, the solid window section 13 and the solid non-window section 17 may prevent the needle from protruding through the cap 9 when the cap 9 is attached to the device 1 .

The cap part 19 may be formed by injection moulding using a first material, for example. The window section 13 may be defined by injection moulding using a second material. The first material may be less transparent than the second material. Accordingly, the cap part 19 and the window section 13 may be formed together in a single 2K injection moulding process. Information located on the cartridge 4 and/or the cartridge holder 3 may be visible through the transparent window section 13. Alternatively, the cap 9 comprising the window section 13 and the non-window section 17 may be formed in an injection moulding process using one single, preferably transparent, material. Therein, the solid cap part 19 may be formed in a first

manufacturing step. The solid cap part 19 may be transparent. In a next step, the at least one window section 13 may be defined by freezing an area of the cap part 19. By means of freezing a predetermined section, e.g. the non-window section 17, of the cap part 19, the non-window section 17 may be made less transparent than the section of the cap part 19 which was not frozen. The non-frozen section may form the window section 13. Accordingly, a transparent section of the cap part 19, i.e. the window section 13, may be defined by freezing.

Freezing of a section of the cap part 19 may allow for a flexible definition of the window section 13, in particular of the shape of the window section 13. A plurality of window sections 13 may be easily defined by abstaining a plurality of predetermined sections from freezing.

Alternatively, the cap 9 may be a two-piece component. The cap 9 may comprise the solid cap part 19 comprising the window section 13 and the non-window section 17. Furthermore, the cap 9 may comprise a solid window insert 14. The respective window insert 14 and the non-window section 17 of the cap part 19 may be, releasably or irreleasably secured, for example glued or snap-fitted, to each other.

According to this embodiment, in a first manufacturing step, the cap part 19 may be formed. The cap part 19 may be formed by injection moulding, for example. Preferably, the cap part 19 is opaque. The cap part 19 is solid. The cap part 19 may have at least one aperture. The position of the aperture may define the position of window section 13 which is to be formed. The aperture may be elongated, for example. In a next step, at least one solid window insert 14 may be formed, e.g. by injection moulding. The solid window insert 14 may be transparent. In particular, the cap part 19 may be less transparent than the at least one window insert 14. The window insert 14 may have a thickness suited to prevent the needle from piercing through the window section 13 of the cap 9 as described previously. The window insert 14 may be adapted and arranged to be introduced into the respective window aperture of the cap part 19. In a next step, the window insert 14 may be inserted in the window aperture. The window insert 14 may be inserted such that the window aperture and, hence, the window section 13 of the cap part 19, is closed by means of the window insert 14. The window insert 14 may be secured, for example snap-fitted, to the cap part 19. The window insert 14 may prevent the needle from piercing through the window section 13 when the cap 9 is attached to the device 1 . The solid window insert 14 may be exchangeable. A plurality of symbols 15 may be printed onto the solid window insert 14. The symbols 15 may be moulded onto the window insert 14, for example. The symbols 15 may relate to a dosage scale for the drug delivery device 1 as described previously. Other implementations are within the scope of the following claims. Elements of different implementations may be combined to form implementations not specifically described herein.

Reference numerals

1 Drug delivery device

2 Housing

3 Cartridge holder

4 Cartridge

5 Engaging means

6 Piston rod

7 Bung

8 Button

9 Cap

10 Distal end

1 1 Proximal end

12 Securing member

13 Window section

14 Window insert

15 Symbol

16 Opening

17 Non-window section

18 Drug

9 Cap part

20 Main longitudinal axis