WO2018068957A1

WO2018068957A1 - Auto injector and a cartridge with interface latches

Info

Publication number: WO2018068957A1
Application number: PCT/EP2017/072488
Authority: WO
Inventors: Flemming Madsen; Jan Olesen; Jørgen RASMUSSEN
Original assignee: H. Lundbeck A/S
Priority date: 2016-10-11
Filing date: 2017-09-07
Publication date: 2018-04-19

Abstract

Disclosed is a plunger lock, and a related cartridge, a related auto injector, and a related system comprising a plunger lock. The plunger lock has a locked state and an unlocked state and is configured to lock a plunger rod to a first stopper of a syringe in the locked state.

Description

AUTO INJECTOR AND A CARTRIDGE WITH INTERFACE LATCHES

The present disclosure relates to an auto injector and a cartridge for an auto injector. In particular, the present disclosure relates to an interface for a connection between an operational component of an auto injector and a plunger of a syringe of a cartridge.

BACKGROUND

Hypodermic syringes are widely used to deliver fluids to the body. It is known to have hypodermic syringes applicable for manual operation. However, auto injectors have been developed and are widely used to aid the administering of fluid or medicaments to the body.

Hygiene and cross contamination are important issues in the field of medical devices, such as auto injectors. Especially devices which, upon usage, may be subject to body fluids provide risks of transferring diseases between patients and between patients and health care providers. Therefore, to prevent contamination from one patient to another, many devices, instruments, and other items in the health care domain are single use. However, technology has provided technical devices including components of high value, and therefore, from a costs perspective, it may be desirable that such devices are not to be thrown away after a single use. Auto injectors in particular are becoming increasingly more and more advanced, and therefore it may be undesirable if such auto injectors are to be thrown away after a single use.

In providing a device, such as an auto injector, to be used a multiple number of times and/or for multiple patients, there is a risk of cross contamination between patients and between patients and health care providers.

It is generally known to perform aspiration, before injecting medicament of a syringe into tissue of a patient, to validate that needle has not been inserted into a blood vessel of the patient. Aspiration involves creating a negative pressure in the syringe thereby retracting a small amount of fluid from the tissue into the syringe. Such aspiration process may reveal if the needle of the syringe has been inserted into a blood vessel, and injection of the medicament into the blood stream may thereby be prevented. SUMMARY

It is an object of the present disclosure to provide an auto injector, such as an electronic auto injector, a related cartridge for an auto injector, and/or a plunger lock, which overcomes at least some of the disadvantages of prior art devices.

The present disclosure provides a cartridge which is simple and therefore may be disposable, and an auto injector that may be usable for multiple injections. As it may be used multiple times, the auto injector may comprise more advanced features. This effect is achieved, at least in part, by the present disclosure.

The present disclosure provides for an auto injector that is capable of performing multiple steps of an injection procedure. Thus, avoid or limit relying on correct user operation of certain tasks.

Accordingly, a plunger lock is provided, especially a plunger lock for a system comprising a plunger rod and a syringe containing a medicament. The plunger lock has a locked state and an unlocked state and being configured to lock the plunger rod to a first stopper of the syringe in the locked state.

Also disclosed is a cartridge for an auto injector. The cartridge comprises a syringe. The syringe comprises a compartment configured for containing a medicament. The syringe has a first syringe end and a second syringe end. The syringe has a syringe opening for fluid communication with the compartment at the first syringe end. The syringe comprises a first stopper movable inside the compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end. The syringe is configured to expel medicament through the syringe opening. The first stopper is configured for being locked to a plunger rod of the auto injector by a plunger lock. The plunger lock has a locked state and an unlocked state and is configured to lock the plunger rod to the first stopper in the locked state.

Also disclosed is an auto injector for administering injection of a medicament. The auto injector comprises a housing, a receiving part, and an operational module.

The receiving part is configured for receiving a cartridge comprising a syringe containing the medicament.

The operational module is configured for interacting with the cartridge. The operational module comprises a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end. The first plunger rod end is proximal to the syringe when the cartridge is received in the receiving part. The operational module is configured for moving a first stopper of the syringe at least in a first stopper direction by movement of the plunger rod in the first stopper direction. The plunger rod is configured for being locked to the first stopper by a plunger lock. The plunger lock has a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

Also disclosed is a system. The system comprises an auto injector and a cartridge. The cartridge comprises a syringe. The syringe comprises a compartment configured for containing the medicament. The syringe has a first syringe end and a second syringe end. The syringe has a syringe opening for fluid communication with the compartment at the first syringe end. The syringe comprises a first stopper movable inside the compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end. The syringe is configured to expel medicament through the syringe opening.

The auto injector comprises a housing, a receiving part and an operational module.

The receiving part is configured for receiving the cartridge.

The operational module is configured for interacting with the cartridge. The operational module comprises a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end. The operational module is configured for moving the first stopper at least in the first stopper direction by movement of the plunger rod in the first stopper direction.

The system comprises a plunger lock. The plunger lock has a locked state and an unlocked state and is configured to lock the plunger rod to the first stopper in the locked state.

Also disclosed is syringe containing a medicament and having a plunger lock. The plunger lock has a locked state and an unlocked state and is configured to lock e.g. a plunger rod to a first stopper of the syringe in the locked state.

The first stopper may be movable, e.g. in the first stopper direction and/or in the second stopper direction, by movement of the plunger rod. The first stopper may be movable in the first stopper direction by movement of the plunger rod in the first stopper direction. The first stopper may be movable in the second stopper direction by movement of the plunger rod in the second stopper direction. For example, when the plunger lock is in the locked state, the first stopper may be movable in the second stopper direction by movement of the plunger rod in the second stopper direction. When the plunger lock is in the locked state, the first stopper may be movable in the first stopper direction by movement of the plunger rod in the first stopper direction. When the plunger lock is in the unlocked state, the first stopper may be movable in the first stopper direction by movement of the plunger rod in the first stopper direction. In one or more embodiments, the first stopper is not movable by the plunger rod in the second stopper direction when the plunger lock is in the unlocked state.

When the plunger rod is locked to the first stopper by the plunger lock, the operational module may be configured for moving the first stopper of the syringe in the second stopper direction by movement of the plunger rod in the second stopper direction.

When the plunger rod is locked to the first stopper by the plunger lock, the operational module may be configured for moving the first stopper of the syringe in the first stopper direction by movement of the plunger rod in the first stopper direction. When the plunger rod is not locked to the first stopper by the plunger lock, the operational module may be configured for moving the first stopper of the syringe in the first stopper direction by movement of the plunger rod in the first stopper direction.

The second stopper direction may be opposite the first stopper direction.

It is an advantage of the present disclosure that it allows the plunger rod, e.g. a plunger rod of the auto injector, to perform both a push and a pull action on the first stopper of the syringe. It may be desired, that a stopper of the syringe, e.g. the first stopper, may be moved both in a first direction and in a second direction. The operational module of the auto injector may thus be configured to perform both a push and a pull action on the first stopper of the syringe, such as via the plunger rod.

It is a further advantage of the present disclosure that it allows an auto injector to provide an aspiration action prior to an injection action.

It is a further advantage of the present disclosure that it allows for increased automation of an injection process.

The plunger lock may be attached to the first stopper, and/or the plunger lock may form a part of the first stopper. Alternatively, the plunger lock may be attached to the plunger rod, and/or the plunger lock may form a part of the plunger rod. It is envisaged that the plunger lock may be formed in co-operation between a plunger lock part being attached to or forming part of the first stopper and a plunger lock part being attached to or forming part of the first stopper. The plunger lock may comprise one or more locking member(s). The plunger lock may comprise at least a first locking member. The first locking member may be configured to be movable between a first primary position and a first secondary position. The plunger lock may comprise a second locking member. The second locking member may be configured to be movable between a second primary position and a second secondary position. The plunger lock may comprise a plurality of locking members including the first locking member and the second locking member.

When the plunger lock is in the unlocked state, a locking member may be in a primary position. When the plunger lock is in the locked state, the locking member may be in a secondary position. For example, when the plunger lock is in the unlocked state, the first locking member may be in the first primary position, and/or the second locking member may be in the second primary position. When the plunger lock is in the locked state, the first locking member may be in the first secondary position, and/or the second locking member may be in the second secondary position.

The syringe comprises a compartment configured for containing the medicament. The syringe has a first syringe end and a second syringe end. The syringe has a syringe opening for fluid communication with the compartment at the first syringe end. A stopper, such as the first stopper, may limit the compartment in the second end whereas the compartment in the first end may be limited by the syringe opening. Thus, the compartment may be confined by compartment walls of the syringe, the stopper, such as the first stopper, and the syringe opening.

The compartment may have an inner compartment wall, e.g. the inside wall of the compartment in contact with the medicament. The inner compartment wall may be in contact with the medicament. The plunger rod may be prevented from touching the inner compartment wall. The risk of contaminating the plunger rod may be limited and/or prevented by preventing the plunger rod from touching the inner compartment wall, and/or to prevent that the plunger rod is contacting substance found on the inner compartment wall, such as medicament residues.

The plunger lock may be configured for centering the plunger rod inside the compartment of the syringe, e.g. so as to align the plunger rod in a center of the syringe, i.e. along a center line of the syringe, thus the plunger lock may be configured such that the plunger rod is prevented from touching the inner compartment wall. The first locking member and/or the second locking member may be configured for centering the plunger rod inside the compartment of the syringe, e.g. the first locking member and/or the second locking member may be configured for preventing the plunger rod from touching the inner compartment wall. A plurality of locking members may provide the centering of the plunger rod inside the compartment of the syringe. Especially in embodiments where the plunger lock is attached to the first stopper and/or forms part of the first stopper, the plunger lock may prevent contamination of the auto injector, such as by preventing contamination of the plunger rod.

The plunger lock may be configured to change state between the unlocked state and the locked state in response to a position of the first stopper in the compartment. For example, the plunger lock may be in the unlocked state when the first stopper is in a first stopper position, and/or the plunger lock may be in the locked state when the first stopper is in a second stopper position. The plunger rod may be locked to the first stopper by the plunger lock when the first stopper is in the second stopper position. The plunger rod may be released or releasable from the plunger lock when the first stopper is in the first stopper position.

A locking member may be in a primary position when the first stopper is in the first stopper position, and/or the locking member may be in a secondary position when the first stopper is in the second stopper position. For example, the first locking member may be in the first primary position when the first stopper is in the first stopper position, and/or the first locking member may be in the first secondary position when the first stopper is in the second stopper position. The second locking member may be in the second primary position when the first stopper is in the first stopper position, and/or the second locking member may be in the second secondary position when the first stopper is in the second stopper position.

The second stopper position may be positioned at a first distance from the first stopper position in the first stopper direction. The first distance may be less than 6 mm, such as less than 4 mm, such as less than 2 mm.

A locking member, such as the first locking member and/or the second locking member may be flexible. For example, a locking member, such as the first locking member and/or the second locking member may be a latch arm, such as a flexible latch arm, or a latch arm comprising a flexible section.

The plunger lock may comprise a plunger lock base. A locking member, such as the first locking member and/or the second locking member, may be connected to the plunger lock base. For example, the locking member, such as the first locking member and/or the second locking member may be a latch arm connected to the plunger lock base, such as a latch arm being flexibly connected to the plunger lock base of the plunger lock.

A locking member may be brought into a secondary position by contact with the inner compartment wall. For example, the first locking member may be brought into the first secondary position by contact with the inner compartment wall. Additionally or alternatively, the second locking member may be brought into the second secondary position by contact with the inner compartment wall.

The plunger lock may be biased towards the unlocked state. The plunger lock may be configured to be in the unlocked state, e.g. when it is not brought into the locked state, and/or when it is not influenced to be in the locked state.

The locking member may be biased towards a primary position. For example, the first locking member may be biased towards the first primary position, and/or the second locking member may be biased towards the second primary position. The locking member, such as the first locking member and/or the second locking member may be biased by flexible means of the locking member, and/or by a spring.

The plunger lock may have a locking part. The locking part may be configured to lock the plunger rod to the first stopper when the plunger lock is in the locked state and/or to unlock the plunger rod from the first stopper when the plunger lock is in the unlocked state. The locking part may have a locking part diameter. The locking part may have a first locking part diameter when the plunger lock is in the unlocked state. The locking part may have a second locking part diameter when the plunger lock is in the locked state. The plunger lock may be configured to change the locking part diameter between the locked state and the unlocked state. The plunger lock may be configured to decrease the locking part diameter when the plunger lock is brought from the unlocked state to the locked state. The first locking part diameter may be larger than the second locking part diameter.

The locking part diameter, such as the first locking part diameter and/or the second locking part diameter may be along a transverse stopper axis, e.g. perpendicular to the stopper axis.

The plunger lock may have a plunger lock receiving part. The plunger lock receiving part may be configured to receive the plunger rod and/or a first plunger rod part of the plunger rod. Alternatively, the plunger lock receiving part may be configured to receive the first stopper and/or a first primary stopper part of the first stopper. The plunger lock receiving part may have a plunger lock receiving part diameter. The plunger lock receiving part diameter may be along an axis perpendicular to the stopper axis, e.g. along the transverse stopper axis.

The compartment may have an inner compartment diameter. The inner compartment diameter may be along an axis perpendicular to the stopper axis, e.g. along the transverse stopper axis.

The plunger lock receiving part diameter may be smaller than the inner compartment diameter. The difference between the plunger lock receiving part diameter and the inner compartment diameter may be larger than a diameter threshold, e.g. larger than 0.3 mm, such as larger than 0.5 mm, such as larger than 1 mm. The difference between the plunger lock receiving part diameter and the inner compartment diameter may be such that plunger rod is prevented from touching the inner compartment wall, and/or to prevent that the plunger rod is contaminated with substance found on the inner compartment wall, such as medicament residues.

The first stopper may be configured to be locked by the plunger lock, e.g. the first stopper may be configured to be locked by the locking part of the plunger lock.

Especially, in embodiments where the plunger lock is attached to the plunger rod, and/or forms part of the plunger rod, the first stopper may be configured to be locked by the plunger rod and/or the locking part of the plunger lock.

The first stopper may have a first primary stopper part. The first primary stopper part may have a first primary stopper diameter. The first primary stopper diameter may be along an axis perpendicular to the stopper axis, such as along the transverse stopper axis. The first primary stopper part may form a protrusion of the first stopper, such as a protrusion for the plunger lock to lock about. The first primary stopper part may be configured to be received in the plunger lock receiving part.

The first stopper may have a first secondary stopper part. The first secondary stopper part may have a first secondary stopper diameter. The first secondary stopper diameter may be along an axis perpendicular to the stopper axis, such as the transverse stopper axis. The first secondary stopper part may be located between the first primary stopper part and the first syringe end. The first secondary stopper part may form a recess in the first stopper, such as a recess for the plunger lock and/or the locking part of the plunger lock to engage. The first primary stopper part diameter may be larger than the first secondary stopper part diameter.

The plunger rod may be configured to be locked by the plunger lock, e.g. the plunger rod may be configured to be locked by the locking part of the plunger lock. Especially, in embodiments where the plunger lock is attached to the first stopper, and/or forms part of the first stopper, the plunger rod may be configured to be locked by the plunger lock and/or the locking part of the plunger lock.

The plunger rod may have a first plunger rod part. The first plunger rod part may have a first plunger rod diameter. The first plunger rod diameter may be along an axis perpendicular to the plunger rod axis, such as along a transverse plunger rod axis and/or the transverse stopper axis. The first plunger rod part may form a protrusion of the plunger rod, such as a protrusion for the plunger lock to lock about. The first plunger rod part may be configured to be received in the plunger lock receiving part. The plunger rod may have a second plunger rod part. The second plunger rod part may have a second plunger rod diameter. The second plunger rod diameter may be along an axis perpendicular to the plunger rod axis, such as along the transverse plunger rod axis and/or the transverse stopper axis. The second plunger rod part may be located between the first plunger rod part and the second plunger rod end. The second plunger rod end may be pointing away from the syringe. The second plunger rod part may form a recess in the plunger rod, such as a recess for the plunger lock and/or the locking part of the plunger lock to engage. The first plunger rod diameter may be larger than the second plunger rod diameter.

The cartridge and/or the system may comprise a syringe casing. The syringe casing may comprise a main body. The main body may be configured for receiving the syringe, and/or the main body may be attached to the syringe. The main body may have a tube part and/or a front end. The tube part may extend along a tube axis.

The syringe may be movable relative to the main body of the syringe casing, when the syringe is received in the main body. For example, the syringe may be movable along the tube axis, e.g. from a first position to a second position relative to the front end of the main body.

The syringe casing may comprise an inner body attachable to the syringe. The main body and/or the tube part may enclose the inner body. The inner body may be movable relative to the main body. For example, the inner body may be movable relative to the main body along the tube axis. The inner body may provide a guided movement of the syringe relative to the main body.

The syringe has a compartment, and the compartment of the syringe may contain the medicament. The medicament may be a fluid and/or a liquid. The medicament may be an aqueous solution, e.g. saline. The medicament may comprise a first medicament component and/or a second medicament component. The compartment may contain the first medicament component and the second medicament component.

The first medicament component and/or the second medicament component may be a powder composition. The first medicament component and/or the second medicament component may be a fluid composition, such as a liquid composition. The first medicament component may be a powder composition and the second medicament component may be a fluid composition, e.g. water or ethanol. The first medicament component may be a solute. The second medicament component may be a solvent. It is envisaged that the medicament may be any medicament being injectable via a syringe, for example after reconstitution of the medicament.

The syringe may be a multi chamber syringe, e.g. the compartment of the syringe may comprise a plurality of compartment parts. For example, the syringe may be a dual chamber syringe, e.g. the compartment of the syringe may comprise a first compartment part and a second compartment part.

Compartment parts may be divided by a stopper, such as a second stopper and/or a third stopper. For example, the syringe may comprise a second stopper between the first syringe end and the first stopper. The second stopper may divide the compartment into a first compartment part and a second compartment part. The second stopper may be movable inside the compartment, e.g. at least in the first stopper direction, such as along the stopper axis. The stopper axis may be parallel or coinciding with the tube axis.

The compartment may comprise one or more bypass sections, such as a middle bypass section and/or a front bypass section. Bypass sections may provide fluid communication between compartment parts when a stopper is positioned in the bypass section. For example, when the second stopper is positioned in the middle bypass section, the first compartment part may be in fluid communication with the second compartment part.

Each of the plurality of compartment parts may comprise a medicament component. The first compartment part may contain the first medicament component. The second compartment part may contain the second medicament component.

In some embodiments, all medicament components, such as for example, the first medicament component and the second medicament component may not need to be physically separated. Thus, providing a plurality of medicament components does not require the compartment to be divided into a plurality of compartment parts. The present device is generally useful for administration of a drug which is injected as a suspension.

The medicament may be a suspension, e.g. a liquid, such as water or an aqueous solution, comprising solid particles of one or more compound(s). The solid particles may be evenly distributed in the liquid. When a medicament is administered as a suspension, the solid particles typically comprise the active ingredient of the medicament, or the main part of the active ingredient. The risk of tissue damage on injection or injection site pain depends on factors such as choice of active ingredient and particle size. The mean particle size of the active ingredient (or other non- dissolved component) can be below 100 μιη, such as 0.5 μιη - 100 μιη, such as 0.5 μιη - 50 μιη, such as 1 μιη - 10 μιη. "mean particle size" refers to volume mean diameter as may be measured by laser-light scattering methods (LLS). Particle size may be measured by LLS methods and mean particle size may be calculated from the particle size distribution. Suspensions can be prepared from a poorly soluble compound and/or compounds, e.g. a compound with a solubility below 0.1 mg/ml in the liquid.

The medicament or an active ingredient of the medicament may comprise a poorly soluble medicament component, such as a medicament component having solubility in the solvent of less than 0.1 mg/ml.

A reusable auto injector, such as the disclosed auto injector, may be especially useful when the syringe comprises more than one compartment or more than one chamber. For example an auto injector for a multi compartment or multi chamber syringe may be more advanced, and therefore it may be beneficial to allow the auto injector to be used more than one time. For example, the auto injector may provide automated processes for mixing medicament components, such as for mixing medicament components initially provided in different compartments of the syringe.

The auto injector may be configured for specific medication and/or specific patients. The auto injector may provide increased possibility for injecting the medicament in certain patients, such as in schizophrenic patients.

The operational module may comprise a stopper operational part. The stopper operational part may be configured for moving a stopper, such as the first stopper. The stopper operational part may be configured for moving the first stopper by movement of the plunger rod in the first stopper direction and/or in the second stopper direction. The stopper operational part may be configured for moving the first stopper at least in the first stopper direction, e.g. to expel medicament through the syringe opening, and/or to advance the medicament towards the first end of the syringe. Furthermore, the stopper operational part may be configured for moving a stopper to a bypass section for allowing mixing of more medicament components positioned in more compartment parts.

The operational module may comprise a syringe operational part. The syringe operational part may be configured for moving the syringe, e.g. along the tube axis. The syringe operational part may be configured for moving a carrier of the operational module. The carrier of the operational module may be attachable to the syringe. The syringe operational part may be configured for moving the syringe to advance a needle of the syringe and/or attached to the syringe, e.g. to insert the needle into tissue of the patient. Alternatively or additionally, the syringe operational part may be configured for moving the syringe to mix a plurality of medicament components, e.g. to obtain a mixed medicament. For example, the syringe operational part may be configured for moving the syringe to mix the first medicament component and the second medicament component to obtain the mixed medicament.

The operational module and/or the auto injector and/or the receiving part may comprise a syringe lock. The syringe lock may have a locked state and an unlocked state. The syringe lock may be configured to lock the syringe to a carrier, such as the carrier of the operational module, in the locked state. The plunger rod may be configured to bring the syringe lock to the unlocked state by a predefined movement in the second stopper direction. For example, a retraction and/or a full retraction of the plunger rod may cause the syringe lock to be in the unlocked state.

The syringe lock may comprise a first syringe locking member. The first syringe locking member may be in a first position when the syringe lock is in the locked state. The first syringe locking member may be in a second position when the syringe lock is in the unlocked state. The first syringe locking member may be biased towards the first position. The plunger rod may be configured to force the first syringe locking member to the second position by a predefined movement in the second stopper direction. For example, a retraction and/or a full retraction of the plunger rod may force the first syringe locking member to the second position.

The syringe lock may comprise a second syringe locking member. The second syringe locking member may be in a first position when the syringe lock is in the locked state. The second syringe locking member may be in a second position when the syringe lock is in the unlocked state. The second syringe locking member may be biased towards the first position. The plunger rod may be configured to force the second syringe locking member to the second position by a predefined movement in the second stopper direction. For example, a retraction and/or a full retraction of the plunger rod may force the second syringe locking member to the second position.

The syringe lock may comprise a plurality of syringe locking members. The plurality of syringe locking members may include the first syringe locking member and the second syringe locking member.

The operational module may comprise a driver and/or a plurality of drivers, such as a stopper driver and/or a syringe driver. The driver(s) may be configured to drive one or more operational part(s) of the operational module. For example, the stopper driver may be configured to drive the stopper operational part and/or the syringe driver may be configured to drive the syringe operational part.

The driver(s), such as the stopper driver and/or the syringe driver, may be a motor, such as an electro-mechanical motor, such as a DC motor, e.g. a DC motor with or without brushes. For example, the stopper driver may be a brushed DC motor and/or the syringe driver may be a brushless DC motor. A brushless DC motor may be preferred due to higher durability of a brushless DC motor. Especially for the syringe driver, a brushless DC motor may be preferred due to many and/or rapid movements performed by the syringe driver. Brushed DC motors are generally cheaper than brushless DC motors. Therefore brushed DC motors may be preferred from a cost perspective. A brushed DC motor may be preferred for the stopper driver.

The auto injector may comprise a processing unit. The processing unit may be connected to the operational module. The processing unit may be configured to operate the operational module, such as the syringe operational part and/or the stopper operational part and/or the stopper driver and/or the syringe driver.

A user of the devices of the present disclosure may be a health care provider and/or a patient. There may be a plurality of users of the devices of the present disclosure, such as a first user and/or a second user and/or a third user. A patient may be a user of the device, e.g. the first user and/or the third user. A health care provider may be a user of the device, e.g. the second user.

In some embodiments the syringe may be manufactured with an attached needle. For example, the needle may be fixedly attached to the syringe. In other embodiments, the syringe and the needle may be manufactured separately, and the user, e.g. a health care provider, may attach the needle before use.

Some embodiments of the present disclosure may include shapes which are not circular. Unless otherwise indicated, a "diameter" of a non-circular shape is the greatest distance between two points on the boundary of the shape.

It is envisaged that any embodiments or elements as described in connection with any one aspect may be used with any other aspects or embodiments, mutatis mutandis. For example, the plunger lock disclosed in relation to the system, cartridge, and/or auto injector may be the plunger lock as also disclosed. The cartridge disclosed in relation to the system may be the cartridge as also disclosed. The auto injector disclosed in relation to the system may be the auto injector as also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present invention will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the attached drawings, in which:

Fig. 1 a-b schematically illustrates exemplary plunger locks,

Fig. 2 schematically illustrates a part of an exemplary system,

Fig. 3 schematically illustrates a part of an exemplary system,

Fig. 4 a-f schematically shows a step by step usage of a part of an exemplary

system,

Fig. 5 schematically illustrates a part of an exemplary system,

Fig. 6 schematically illustrates a part of an exemplary system,

Fig. 7 schematically illustrates an exemplary first stopper,

Fig. 8 a-b schematically illustrates an exemplary syringe lock,

Fig. 9 schematically illustrates an exemplary syringe lock and an exemplary syringe,

Fig. 10 schematically illustrates an exemplary syringe,

Fig. 1 1 shows an exploded view of an exemplary cartridge,

Fig. 12 schematically illustrates an exemplary system,

Fig. 13 schematically illustrates an exemplary operational module, and Fig. 14 schematically illustrates an exemplary system.

DETAILED DESCRIPTION

Various embodiments are described hereinafter with reference to the figures. Like reference numerals refer to like elements throughout. Like elements will, thus, not be described in detail with respect to the description of each figure. It should also be noted that the figures are only intended to facilitate the description of the embodiments. They are not intended as an exhaustive description of the claimed invention or as a limitation on the scope of the claimed invention. In addition, an illustrated embodiment needs not have all the aspects or advantages shown. An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated, or if not so explicitly described.

Throughout, the same reference numerals are used for identical or corresponding parts.

A plunger rod is throughout the present disclosure to be understood as any means capable of moving a stopper of a syringe in a first and/or second direction. The plunger rod may form part of an auto injector.

Figs. 1 a-b schematically illustrates two exemplary plunger locks 202. The plunger lock 202 has a locked state and an unlocked state and is configured to lock a plunger rod, such as a plunger rod of an auto injector, to a first stopper of a syringe in the locked state.

The plunger lock 202 comprises a first locking member 204 and a second locking member 206. As illustrated in Fig. 1 b. The plunger lock 202 may comprise a plurality of locking members, e.g. including the first locking member 204 and the second locking member 206.

The locking member(s), such as the first locking member 204 and/or the second locking member 206, is configured to be movable between a primary position and a secondary position. For example, the first locking member 204 is configured to be movable between a first primary position and a first secondary position, and/or the second locking member 206 is configured to be movable between a second primary position and a second secondary position. The locking member(s) 204, 206 may be in the primary position when the plunger lock 202 is in the unlocked state, and/or the locking member(s) 204, 206 may be in the secondary position when the plunger lock 202 is in the locked state. For example, the first locking member 204 may be in the first primary position when the plunger lock 202 is in the unlocked state, and/or the first locking member 204 may be in the first secondary position when the plunger lock 202 is in the locked state. Additionally or alternatively, the second locking member 206 may be in the second primary position when the plunger lock 202 is in the unlocked state, and/or the second locking member 206 may be in the second secondary position when the plunger lock 202 is in the locked state.

To be movable between primary and secondary positions, the locking member(s) 204, 206 may be flexible. The locking member(s) 204, 206 may flex inwardly, e.g. towards the center, and/or outwardly, e.g. away from the center.

The locking member(s) 204, 206 may be biased towards a position, such as the primary position, e.g. the primary position, such as the first primary position and/or the second primary position, may be a relaxed position, such as a position that the locking member(s) 204,206 attain when not influenced by other parts.

The plunger lock 202 comprises a plunger lock base 203. The plunger lock base 203 may be configured for attaching the plunger lock to the first stopper, e.g. the plunger lock 202 may be attached to the first stopper by a screw extending through a hole in the plunger lock base 203. Alternatively, the plunger lock base 203 may be configured for attaching the plunger lock to the plunger rod, e.g. the plunger lock 202 may be attached to the first stopper by a screw extending through a hole in the plunger lock base 203.

The locking member(s), such as the first locking member 204 and/or the second locking member 206, is attached to the plunger lock base 203, e.g. the locking member(s) 204, 206 may be hingedly attached to the plunger lock base 203 as illustrated in Fig. 1 b.

Fig. 2 schematically illustrates a part of an exemplary system 400. The system 400 comprises a syringe 100, a plunger rod 314, such as a plunger rod 314 of an auto injector (not shown), and a plunger lock 202.

The syringe 100 comprises a compartment 102 configured for containing a medicament. The syringe has a first syringe end 104 and a second syringe end 106. The syringe has a syringe opening 108 for fluid communication with the compartment 102. The syringe opening 108 is at the first syringe end 104.

The syringe 100 comprises a first stopper 1 12 movable inside the compartment 102. The first stopper 1 12 is movable along a stopper axis 512 in a first stopper direction 502 towards the first syringe end 104. The first stopper 1 12 may further be movable in a second stopper direction towards the second syringe end 106, e.g. the first stopper 1 12 may be retracted towards the second syringe end 106 when in an advanced position in the compartment 102.

The syringe 100 is configured to expel medicament through the syringe opening 108. For example, the medicament may be expelled through the syringe opening 108 upon movement of the first stopper 1 12 in the first stopper direction. Additionally or alternatively, the syringe 100 may be configured to aspirate fluid through the syringe opening 108. For example, the first stopper 1 12 may be moved in the second stopper direction, to aspirate fluid through the syringe opening 108. Movement of the first stopper 1 12 in the second stopper direction may generate a negative pressure in the compartment 102 facilitating aspiration through the syringe opening 108.

The plunger lock 202 is configured to lock the plunger rod 314 to the first stopper in the locked state. The plunger rod 314 extends along a plunger rod axis 516. The plunger rod 314 has a first plunger rod end proximal to the syringe 100, such as proximal to the first stopper 1 12 of the syringe 100.

The plunger rod 314 is configured to move the first stopper 1 12 in the first stopper direction 502. When the plunger rod 314 is locked to the first stopper 1 12 by the plunger lock 202, movement of the plunger rod 314 in the second stopper direction facilitates movement of the first stopper 1 12 in the second stopper direction. Thus, the plunger lock 202 facilitates movement of the first stopper in the second stopper direction, e.g. an aspiration movement of the first stopper 1 12, by movement of the plunger rod 314 in the second stopper direction.

The plunger lock 202 may be connected and/or fastened and/or attached to the first stopper 1 12. The first stopper 1 12 may be configured for attachment of the plunger lock 202. For example, the first stopper 1 12 may be provided with a hole adapted to receive a screw for fastening the plunger lock 202 to the first stopper 1 12.

Fig. 3 schematically illustrates a cross-sectional view of a part of an exemplary system 400. The system 400 comprises a syringe 100, a plunger lock 202, and a plunger rod 314. The syringe 100 comprises a compartment 102. The compartment has a compartment wall with an inner compartment wall 1 18 and an outer compartment wall 120. The compartment has an inner compartment diameter 122.

The syringe 100 also comprises a first stopper, as described in relation to other figures, but omitted from the current figure for intelligibility.

The plunger rod 314 has a first plunger rod part 318. The first plunger rod part 318 has a first plunger rod diameter 324. The plunger rod 314 has a second plunger rod part 320. The second plunger rod part 320 has a second plunger rod diameter 326. The first plunger rod diameter 324 is larger than the second plunger rod diameter 326.

The plunger lock 202 comprises a plunger lock base 203, and a first locking member 204 and a second locking member 206.

The plunger lock 202 has a plunger lock receiving part 220. The plunger lock receiving part 220 has a plunger lock receiving part diameter 214. The plunger lock receiving part 220 is provided by the plunger lock base 203, the first locking member 204 and the second locking member 206. The plunger lock receiving part 220 is configured to receive the first plunger rod part 318. The plunger lock receiving part diameter 214 may be equal to or larger than the first plunger rod diameter 324.

The first plunger rod diameter 324 may be such that the first plunger rod part 318 and/or the plunger rod 314 do not touch the inner compartment wall 1 18, e.g. the first plunger rod diameter 324 may be such that a difference between the first plunger rod diameter 324 and the inner compartment diameter 122 is larger than a diameter threshold, such as more than 0.5 mm, such as more than 1 mm.

The plunger lock receiving part diameter 214 may be such that the first plunger rod part 318 and/or the plunger rod 314 is prevented from touching the inner compartment wall 1 18, e.g. the plunger lock receiving part diameter 214 may be such that a difference between the plunger lock receiving part diameter 214 and the inner compartment diameter 122 is larger than the diameter threshold, such as more than 0.5 mm, such as more than 1 mm.

Preventing the plunger rod 314 and/or the first plunger rod part 318 from touching the inner compartment wall 1 18 reduce the risk of contaminating the plunger rod 314.

The plunger lock 202 has a locking part 208. The locking part is configured to be altered between the locked state and the unlocked state of the plunger lock 202. The locking part 208 has a locking part diameter 212. The locking members 204, 206 are configured to deflect inwardly, thereby decreasing the locking part diameter 212 when the plunger lock 202 is brought into the locked state. The locking part 208 has a first locking part diameter when the plunger lock 202 is in the unlocked state, and/or the locking part 208 has a second locking part diameter when the plunger lock 202 is in the locked state. The first locking part diameter may be larger than the second locking part diameter.

The first locking part diameter is larger than the plunger lock receiving part diameter 214, and/or the first locking part diameter is larger than the first plunger rod diameter 324, to allow the first plunger rod part 318 to access or exit the plunger lock receiving part 210.

The second locking part diameter is smaller than the plunger lock receiving part diameter 214, and/or the second locking part diameter is smaller than the first plunger rod diameter 324, to retain the first plunger rod part 318 in the plunger lock receiving part 210.

The first locking member 204 has first thickness. The first locking member 204 has a first primary thickness 220 and a first secondary thickness 222. The first secondary thickness 222 is larger than the first primary thickness 220. The first locking member 204 is configured to deflect inwards when the plunger lock 202 is brought into the locked state. The first secondary thickness 222 provides that the locking part diameter 212 is smaller than the plunger lock receiving part diameter 214 when the plunger lock 202 is in the locked state, i.e. the second locking part diameter is smaller than the plunger lock receiving part diameter 214.

The locking part 208 has a locking part outer diameter 216. When the plunger lock 202 is in the unlocked state (as shown), the locking part 208 has a first locking part outer diameter. The inner compartment diameter 122 is smaller than the first locking part outer diameter. When the plunger lock 202 is advanced into the compartment 102, the inner compartment wall 1 18 abut the first and/or second locking member(s) 204, 206, thereby decreasing the locking part outer diameter 216 to a second locking part outer diameter. The second locking part outer diameter may be equal to the inner compartment diameter 122. The second locking part outer diameter is smaller than the first locking part outer diameter.

The first primary thickness 220 is such that the sum of two times the first primary thickness 220 and the first plunger rod diameter 324 is less than the inner compartment diameter 122. For example: 2 x first primary thickness + first plunger rod diameter

<

inner compartment diameter

The first secondary thickness 222 is such that the sum of two times the first secondary thickness 222 and the first plunger rod diameter 324 is larger than, or much larger than, the inner compartment diameter 122. For example:

2 x first secondary thickness + first plunger rod diameter

»

inner compartment diameter

This may ensure that the plunger rod 314 is locked by the plunger lock 202, when the plunger lock 202 is in the locked state, e.g. when the plunger lock 202 is enclosed in the compartment 102.

The first locking member 204 comprises a first locking surface 205. The second locking member 206 comprises a second locking surface. The locking surface(s) changes angle due to deflection of the locking member(s). When the plunger lock 202 is in the locked state, such as when the plunger lock 202 is inside the compartment 102, the first locking surface 205 should be as close to perpendicular to the inner compartment wall 1 18 to avoid excessive friction to the inner compartment wall 1 18, e.g. The angle may preferably be in the range 105-135 degrees when the first locking member is in the first secondary position and/or when the plunger lock is in the locked state. When the plunger lock 202 is in the unlocked state, such as when the plunger lock 202 is not enclosed in the compartment 102, the locking surface 205 should be at an angle to ensure that the plunger rod 314 can be pulled out of the plunger lock, once the plunger lock is not enclosed in the compartment 102.

The length of the locking member(s) may be as short as possible to avoid long and fragile locking member(s), and to avoid taking up more space than necessary.

However, the arms may be long enough to allow sufficient flexibility to deflect without over stressing the material. The length of the locking member may be in the range 4-10 mm.

In the example depicted, the first locking member 204 and the second locking member 206 are similar. Thus, the description with regards to the first locking member 204 is also applicable to the second locking member 206. However, in other embodiments, the plunger lock 202 may comprise a plurality of different locking members. The inner compartment diameter 122, the plunger lock receiving part diameter 214, the locking part diameter 212, the locking part outer diameter, the first plunger rod diameter 324, and/or the second plunger rod diameter 326 may be along a transverse stopper axis perpendicular to the stopper axis as shown and described in relation to other figures.

Fig. 4a-f schematically shows a step by step usage of a part of an exemplary system 400. The system 400 comprises a syringe 100, a plunger rod 314, and a plunger lock 202.

The syringe 100 comprises a compartment 102 containing a medicament 126. The syringe has a first syringe end 104 and a second syringe end 106. The syringe has a syringe opening 108 for fluid communication with the compartment 102. A needle 1 16, such as a hypodermic needle, is attached to the syringe 100. The syringe 100 is configured to expel medicament through the needle 1 16 and/or the syringe opening 108.

The syringe 100 comprises a first stopper 1 12 movable inside the compartment 102. The first stopper 1 12 is movable along a stopper axis in a first stopper direction towards the first syringe end 104 and in a second stopper direction towards the second syringe end 106. The medicament 126 may be expelled through the syringe opening 108 and/or the needle 1 16 upon movement of the first stopper 1 12 in the first stopper direction.

Additionally or alternatively, the syringe 100 may be configured to aspirate fluid through the syringe opening 108. For example, the first stopper 1 12 may be moved in the second stopper direction, to aspirate fluid through the syringe opening 108. Movement of the first stopper 1 12 in the second stopper direction may generate a negative pressure in the compartment 102 facilitating aspiration through the syringe opening 108.

The plunger lock 202 is configured to lock the plunger rod 314 to the first stopper 1 12. The plunger lock 202 is attached to the first stopper 1 12. The plunger lock 202 has a locked state and an unlocked state. The plunger lock 202 is configured to lock the plunger rod to the first stopper in the locked state. The plunger lock 202 comprises a first locking member 204. The plunger lock 202 comprises a second locking member 206.

The first locking member 204 and/or the second locking member 206, is configured to be movable between a first primary position and a first secondary position. The plunger rod 314 comprises a first plunger rod part 318 and a second plunger rod part 320. The first plunger rod part 318 has a first plunger rod diameter. The second plunger rod part 320 has a second plunger rod diameter. The first plunger rod diameter is larger than the second plunger rod part.

Fig. 4a shows a moment where the plunger rod 314 is engaging towards the syringe 100. The first stopper 1 12 is in a first stopper position. The plunger lock 202 is in the unlocked state. The first locking member 204 is in the first primary position. The second locking member 206 is in the second primary position. The locking part of the plunger lock 202 has a first locking part diameter which is larger than the first plunger rod diameter of the first plunger rod part 318.

Fig. 4b shows a moment where the plunger rod 314 has engaged the syringe 100. The first plunger rod part 318 is received in the plunger lock receiving part 210 of the plunger lock 202. The plunger rod 314 has moved the first stopper 1 12 a first distance to a second stopper position in the first stopper direction. The plunger lock 202 is in the locked state. The plunger rod 314 is locked to the first stopper 1 12 by the plunger lock 202.

The first locking member 204 is in the first secondary position. The first locking member 204 is abutting the inner compartment wall 1 18 of the compartment. The first locking member 204 is brought into the first secondary position by contact with the inner compartment wall 1 18. The second locking member 206 is in the second secondary position. The second locking member 206 is abutting the inner compartment wall 1 18 of the compartment. The second locking member 206 is brought into the second secondary position by contact with the inner compartment wall 1 18.

Deflection of the locking members 204, 206, caused by abutment to the inner compartment wall, the locking part of the plunger lock 202 has a second locking part diameter which is smaller than the first plunger rod diameter of the first plunger rod part 318. The locking part diameter has been decreased. The second locking part diameter is smaller than the first locking part diameter.

Fig. 4c shows a further movement of the first stopper 1 12, plunger rod 314 and the plunger lock 202 in the first stopper direction. For example, this movement may be an air shot, i.e. to deplete air from the compartment 102 and/or needle 1 16. The movement of the first stopper 1 12 in the first stopper direction is caused by the plunger rod 314 advancing in the first stopper direction. The plunger rod 314 pushes the first stopper 1 12. Fig. 4d shows that the first stopper 1 12 has been retracted and/or the first stopper 1 12 has moved in the second stopper direction, e.g. away from the needle 1 16 and/or opening 108. For example, this movement may be aspiration of fluid, e.g. to determine if the needle has been inserted into a blood vessel. The movement of the first stopper 1 12 in the second stopper direction is caused by the plunger rod moving the in second stopper direction. The plunger rod 314 pulls the first stopper 1 12. The plunger lock 202 provides that the plunger rod 314 is capable of pulling the first stopper 1 12. The plunger rod being locked to the first stopper 1 12 by the plunger lock 202 in the locked position provides that the first stopper 1 12 follows the plunger rod 314 when the plunger rod is retracted and/or moved in the second stopper direction.

Fig. 4e shows that the first stopper 1 12 is moved in the first stopper direction to expel the medicament 126. The movement of the first stopper 1 12 in the first stopper direction to expel the medicament 126 is caused by the plunger rod 314 advancing in the first stopper direction. The plunger rod 314 pushes the first stopper 1 12.

Fig. 4f shows that the first stopper 1 12 and the plunger lock 202 are retracted and/or moved in the second stopper direction, e.g. to the second syringe end 106 and/or to the first stopper position. The plunger lock 202 is in the unlocked state. The plunger lock 202 has changed state due to reaching the second syringe end 106, such that the locking members 204, 206 are no longer restricted by the inner compartment wall 118. The locking members 204, 206 are no longer deflected by the inner compartment wall 1 18. The plunger rod 314 is no longer locked to the first stopper 1 12 by the plunger lock 202. The plunger rod 314 may be retracted further, e.g. away from the first stopper 1 12.

Fig. 5 schematically illustrates a part of an exemplary system 400' comprising a syringe 100', a plunger lock 202 and a plunger rod 314. The plunger lock 202 is attached to the plunger rod 314. The first stopper 112' of the syringe 100' is configured to be locked to the plunger rod 314 by the plunger lock 202.

The first stopper 1 12' has a first primary stopper part 142 and a first secondary stopper part 144. The first secondary stopper part 144 is located between the first primary stopper part 142 and the first syringe end 104.

The first primary stopper part 142 has a first primary stopper part diameter. The first secondary stopper part 144 has a first secondary stopper part diameter. The first primary stopper part diameter and/or the first secondary stopper part diameter may be along a transverse stopper axis perpendicular to the stopper axis as shown and described in relation to other figures. The first primary stopper part diameter is larger than the first secondary stopper part diameter.

The system 400' works similarly to the system as described in relation to Fig. 4a-f. However, the system 400 of Fig. 4a-f has the additional advantage that the plunger rod 314 does not come in contact with the inner compartment wall 1 18. Thereby, the risk of contamination of the plunger rod is decreased.

Fig. 6 schematically illustrates a part of an exemplary system 400" comprising a syringe 100', a plunger lock 202' and a plunger rod 314. The plunger lock 202' is attached to the plunger rod 314. The first stopper 112' of the syringe 100 is configured to be locked to the plunger rod 314 by the plunger lock 202'.

The plunger lock 202' may be configured to change between the locked state and the unlocked state by an electrical and/or a mechanical impact, such as via an electrical signal, via a user interaction, etc. The electrical and/or mechanical impact may be performed automatically or may be user initiated. For example, a first locking member 204 of the plunger lock 202' may be biased, such as spring biased, towards a first secondary position and/or a second locking member 206 of the plunger lock 202' may be biased towards a second secondary positon. An electrical signal may activate an electro-magnet, such that the first locking member 204 is brought to a first primary position and/or an electrical signal may activate an electro-magnet, such that the second locking member 206 is brought to a second primary position. Thus, an electrical signal may cause the plunger lock 202' to change state from a locked state to an unlocked state. Alternatively, the plunger lock 202' may be configured to change between the locked state and the unlocked state by movement and/or position of the plunger lock 202' and/or the plunger rod 314. For example, the first locking member 204 of the plunger lock 202' may be biased, such as spring biased, towards the first secondary position and/or the second locking member 206 of the plunger lock 202' may be biased towards a second secondary positon. The first locking member 204 may be brought to the first primary position by retraction of the plunger lock 202', and/or the second locking member 206 may be brought to the second primary position by retraction of the plunger lock 202'. For example, a rigid body (not shown) may interact with or impact the hind part of the first locking member 204 and/or the second locking member 206, such that when the plunger lock 202' is retracted into the rigid body, the first locking member 204 is brought into the first primary position, and/or the second locking member 206 is brought into the second primary position.

Fig. 7 schematically illustrates an exemplary first stopper 1 12' of a syringe 100'. The first stopper 1 12' of the syringe 100 is configured to be locked to a plunger rod by a plunger lock.

The first stopper 1 12' has a first primary stopper part 142 and a first secondary stopper part 144. The first secondary stopper part 144 is located between the first primary stopper part 142 and a first syringe end.

The first primary stopper part 142 has a first primary stopper part diameter 146. The first secondary stopper part 144 has a first secondary stopper part diameter 148. The first primary stopper part diameter 146 is larger than the first secondary stopper part diameter 148. The first primary stopper part diameter 146 and the first secondary stopper part diameter 148 are smaller than an inner compartment diameter 122 of the syringe 100'.

The first primary stopper part diameter 146 and/or the first secondary stopper part diameter 148 and/or the inner compartment diameter 122 may be along a transverse stopper axis perpendicular to the stopper axis as shown and described in relation to other figures.

Fig. 8a-b schematically illustrates an exemplary syringe lock 366. The auto injector and/or the operational module of the auto injector, as described in relation to other figures, may comprise the syringe lock 366. The syringe lock 366 has a locked state, as shown in Fig. 8a, and an unlocked state, as shown in Fig. 8b. The syringe lock 366 is configured to lock a syringe to a carrier of the operational module in the locked state.

The syringe lock 366 comprises a first syringe locking member 368. The first syringe locking member 368 is in a first position when the syringe lock 366 is in the locked state, as shown in Fig. 8a. The first syringe locking member 368 is in a second position when the syringe lock 366 is in the unlocked state, as shown in Fig. 8b. The first syringe locking member 368 is biased towards the first position by a first syringe locking member spring 372. The first syringe locking member 368 is configured to be forced towards the second position by a plunger rod 314, such as a plunger rod of the auto injector.

The syringe lock 366 comprises a second syringe locking member 370. The second syringe locking member 370 is in a first position when the syringe lock 366 is in the locked state, as shown in Fig. 8a. The second syringe locking member 370 is in a second position when the syringe lock 366 is in the unlocked state, as shown in Fig. 8b. The second syringe locking member 370 is biased towards the first position by a second syringe locking member spring 374. The second syringe locking member 370 is configured to be forced towards the second position by the plunger rod 314.

The syringe lock 366 may in other embodiments comprise a plurality of locking members, such as a third and/or a fourth and/or a fifth syringe locking member. One or more of the plurality of locking members may be locking members such as the first locking member 368 and/or the second locking member 370.

The plunger rod 314 is configured to force the first syringe locking member 368 and the second syringe locking member 370 to the second position by a predefined movement, such as a predefined movement in a second stopper direction. For example, as illustrated, the plunger rod 314 is configured to force the first syringe locking member 368 and the second syringe locking member 370 to the second position by retracting the plunger rod 314.

The plunger rod 314 has a first plunger rod part 318 and a second plunger rod part 320. The first plunger rod part 318 has a first plunger rod diameter and the second plunger rod part 320 has a second plunger rod diameter. The first plunger rod diameter is larger than the second plunger rod diameter.

When the plunger rod 314 is in a retracted position, as shown in Fig. 8b, the first plunger rod part 318 contacts a surface of the first syringe locking member 368, and the first plunger rod part 318 contacts a surface of the second syringe locking member 370. The first syringe locking member 368 and the second syringe locking member 370 are forced to the second position by the contact with the first plunger rod part 318. Thereby is the syringe lock 366 in the unlocked state.

When the plunger rod 314 is in an advanced position, as shown in Fig. 8a, the second plunger rod part 320 is near the surface of the first syringe locking member 368 and the surface of the second syringe locking member 370. The second plunger rod part 320, having a second plunger rod diameter smaller than the first plunger rod diameter, allows the first syringe locking member spring 372 to force the first syringe locking member 368 into the first position, and the second syringe locking member spring 374 to force the first syringe locking member 370 into the first position.

Upon retraction of the plunger rod 314, the syringe lock 366 is brought to the unlocked state. Upon advancement of the plunger rod 314, the syringe lock 366 is brought to the locked state.

Fig. 9 schematically illustrates an exemplary syringe lock 366 engaging and/or releasing a syringe 100.

The plunger rod 314 is in a retracted position. The syringe lock 366 is in the unlocked position. The first syringe locking member 368 and the second syringe locking member 370 are in the first position.

The syringe 100 comprises a compartment 102 configured for containing a

medicament. The syringe 100 has a first syringe end 104 and a syringe opening 108 at the first syringe end 104. The syringe 100 is configured to expel medicament through the syringe opening 108. The syringe comprises a first stopper 1 12, a second stopper 1 14 and a third stopper 1 15. The first stopper 1 12, the second stopper 1 14, and the third stopper 1 15 are movable inside the compartment 102.

The syringe 100 comprises a first syringe lock receiver 150 and a second syringe lock receiver 152. The first syringe lock receiver 150 is configured for engagement with the first syringe locking member 368. The second syringe lock receiver 152 is configured for engagement with the second syringe locking member 370. The first syringe lock receiver 150 and/or the second syringe lock receiver 152 may be formed in an outer compartment wall 120 of the compartment 102. Alternatively or additionally, the first syringe lock receiver 150 and/or the second syringe lock receiver 152 may be formed in a syringe lock body attached to compartment wall 120. For example, the first syringe lock receiver 150 and/or the second syringe lock receiver 152 may be formed in an external body fixedly attached to the compartment 102.

Fig. 10 schematically illustrates an exemplary syringe 100. The syringe 100 may be attached to a syringe casing 2 as described in relation to other figures. The syringe 100 comprises a compartment 102 configured for containing a medicament 126. In the depicted example, the syringe 100 is a dual chamber syringe and the medicament 126 is comprised by a first medicament component 128, e.g. a powder or cake composition, and a second medicament component 130, e.g. a fluid or a liquid component. In other embodiments, the medicament 126 may be a single component and/or the syringe 100 may be a single chamber syringe or the syringe 100 may have a plurality of chambers higher than two.

The syringe 100 has a first syringe end 104 and a second syringe end 106. The syringe 100 extends along a syringe axis 530 between the first syringe end 104 and the second syringe end 106. The syringe has a syringe opening 108 at the first syringe end 104. The syringe opening 108 provides fluid communication with the compartment 102. The syringe 100 is configured to expel the medicament 126 through the syringe opening 108. The syringe 100 comprises an optional first syringe channel 1 10, and the syringe 100 is configured to expel the medicament 126 through the first syringe channel 1 10. The syringe opening 108 is a syringe opening of the first syringe channel 1 10.

The syringe 100 comprises a first stopper 1 12 movable inside the compartment 102. The first stopper 1 12 is movable at least in a first stopper direction 502 from the second syringe end 106 towards the first syringe end 104. The first stopper 1 12 may be movable in a second stopper direction 503. The second stopper direction 503 may be opposite the first stopper direction 502.

The syringe 100, as depicted, furthermore comprises an optional second stopper 1 14 between the first syringe end 104 and the first stopper 1 12. The second stopper 1 14 is movable inside the compartment 102. The second stopper 1 14 is movable at least in a first stopper direction 504 for the second stopper 1 14. As depicted, the first stopper direction 504 for the second stopper 1 14 may be the same direction as the first stopper direction 502. The second stopper divides the compartment 102 into a first

compartment part 134 and a second compartment part 136. The first compartment part 134 contains the first medicament component 128. The second compartment part 136 contains the second medicament component 130. The compartment 102 furthermore comprises a middle bypass section 138. The middle bypass section 138 provides the possibility for fluid communication between the first compartment part 134 and the second compartment part 136, thereby providing that the first medicament component 128 may be combined with the second medicament component 130. When the second stopper 1 14 is positioned in the middle bypass section 138 the first compartment part 134 is in fluid communication with the second compartment part 136. In embodiments wherein the second stopper 1 14 is omitted, the middle bypass section 138 may also be omitted. The syringe 100, as depicted, furthermore comprises an optional third stopper 1 15 between the first syringe end 104 and the second stopper 1 14. The third stopper 1 15 is movable inside the compartment 102. The third stopper 1 15 is movable at least in a first stopper direction 505 for the third stopper 1 15. As depicted, the first stopper direction 505 for the third stopper 1 15 may be the same direction as the first stopper direction 502 for the first stopper 1 12 and/or the first stopper direction 504 for the second stopper 1 14. The third stopper 115 provides a seal between a compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, from the syringe opening 108. The compartment 102 furthermore comprises a front bypass section 139. The front bypass section 139 provides the possibility for fluid communication between the compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, and the syringe opening 108. When the third stopper 1 15 is positioned in the front bypass section 139 the compartment part containing the medicament 126, such as the first compartment part 134 and/or the second compartment part 136, is in fluid communication with syringe opening 108 to allow the medicament 126 to be expelled through the syringe opening 108. In embodiments wherein the third stopper 1 15 is omitted, the front bypass section 139 may also be omitted.

The first stopper 1 12, the second stopper 1 14, and/or the third stopper 1 15 may be movable along a stopper axis 512. The first stopper direction 502 for the first stopper 1 12, the first stopper direction 504 for the second stopper 114, and/or the first stopper direction 505 for the third stopper 1 15 may be along the stopper axis 512. The stopper axis 512 may, as illustrated, be parallel and/or coinciding with the syringe axis 530. Fig. 1 1 shows an exploded view of an exemplary cartridge 200 for an auto injector. The cartridge 200 comprises a syringe casing 2 and a syringe 100.

The syringe casing 2 comprises a main body 4 and an inner body 16. The main body 4 has a tube part 6 and a front end 10.

The syringe casing 2 comprises an optional cover element 24. The cover element 24 has a cover part 26 and a cover opening 28. The cover element 24 is movable relative to the front end 10 between a first position and a second position. In the example depicted, the cover element 24 is in the first position. In the second position (not shown), the cover part 26 covers at least a portion of the front end opening, and the cover opening 28 and the front end opening 12 forms a covered main body opening for allowing passage of a needle, e.g. a needle attached to the syringe 100. A removable sheet 20 may be configured to cover at least a part of a cover surface 40 of the cover element 24, and/or the removable sheet 20 may be configured to completely cover the cover surface 40 of the cover element 24. When the cover part 26 is in the second position, the cover surface 40 may form the front surface 22 of the front end 10.

The syringe casing 2 comprises an optional locking element 18. In the depicted example, the inner body 16 comprises the locking element 18. The locking element 18 is configured for preventing the inner body 16 from moving towards the front end 10, when the inner body 16 is in a locked position, e.g. in a fully retracted position.

The syringe 100 comprises a first syringe end 104 and a second syringe end 106. The syringe 100 may comprise an optional syringe cap 140 at the first syringe end 104. The syringe cap 140 may be removable, and provided for protection of the medicament contained in the syringe. For example, the syringe cap 140 may be configured for covering a syringe opening of the syringe 100. The cover element 24 of the syringe casing 2 provides needle protection in situations where the syringe 100 is fitted with a syringe cap 140, and therefore is not able to fit through an opening which fulfils the requirements for needle protection. Furthermore, the cover element 24 provides that the syringe 100 may be front loaded into the syringe casing 2, where after the cover element 24 may be used to reduce the size of the opening to fulfil requirements for needle protection.

The cartridge comprises a plunger lock 202. The plunger lock 202 is configured to be fastened to a first stopper of the syringe 100. The plunger lock 202 is configured to be fasted to the first stopper by a plunger lock fastener 228, e.g. a screw. The plunger lock 202 is configured to lock the first stopper to a plunger rod in a locked state.

As depicted, both syringe 100 and the syringe casing 2, such as the main body 4, the tube part 6, and/or the inner body 16, may extend along the same longitudinal axis, e.g. the tube axis 500.

Fig. 12 schematically illustrates an exemplary system 400, 400', 400" comprising an auto injector 300 and a cartridge 200 comprising a syringe 100 containing a

medicament. The cartridge 200 is configured to be received in the auto injector 300, and the auto injector 300 is configured for administering injection of the medicament contained in the syringe 100 of the cartridge 200. The auto injector 300 may be used multiple times. The cartridge 200 may be discarded after use, e.g. after each use, and a new cartridge 200 may be inserted into the auto injector 300 for a subsequent use. The auto injector 300 comprises a housing 302 and a receiving part 304 configured for receiving the cartridge 200. The auto injector 300 furthermore comprises an operational module (not visible) configured for interacting with the cartridge 200. The operational module may be enclosed in the housing 302.

The cartridge 200 comprises the syringe 100 and a syringe casing 2, which have been further described in relation to other figures.

The tube part 6 extends along the tube axis 500, and the tube part has a tube part outer perimeter 8 in a first tube plane perpendicular to the tube axis. The front end 10 has a front end outer perimeter 14 in a second tube plane perpendicular to the tube axis. The auto injector comprises a housing front part 354. The housing front part 354 has a housing front part outer perimeter 356 in a third tube plane perpendicular to the tube axis 500, such as when the cartridge 200 is received in the receiving part 304 of the auto injector 300.

The front end outer perimeter 14 circumscribes an area larger than, or equal to, an area circumscribed by the housing front part outer parameter 356. The front end 10 covers, and/or completely covers, the housing front part 354 when the cartridge 200 is received in the receiving part 304. This decreases the risk of contaminating the auto injector 300, which is especially important if the auto injector 300 is to be used by multiple users, e.g. patients.

The front end outer perimeter 14 circumscribes an area larger than an area

circumscribed by the tube part outer parameter 8. Thereby, the cartridge 200 may be suitable for front loading into the auto injector 300 as the front end 10 provides a stop for inserting the cartridge into the receiving part 304 of the auto injector 300.

The auto injector 300 comprises an optional display unit 350 for visually displaying information to a user of the auto injector, e.g. to a health care provider. The auto injector 300 comprises an optional user interface 358 for receiving a user input from a user of the auto injector, e.g. a health care provider. The user interface 358 may, as also illustrated, comprise one or more push buttons.

The auto injector 300 comprises a processing unit 330, the processing unit 330 being configured to control the operation of the auto injector, including the operation of the operational module.

Fig. 13 schematically illustrates an exemplary operational module 306 for an auto injector, such as the auto injector 300 as described in relation to other figures. The operational module 306 is configured for interacting with a cartridge, such as the cartridge 200 as described in relation to other figures. The operational module 306 comprises a carrier 308 for attaching to a syringe, such as the syringe 100 as described in relation to other figures.

The operational module 306 comprises a stopper operational part 310. The stopper operational part 310 is configured for moving a stopper of the syringe, such as a first stopper of the syringe. In the depicted example, the stopper operational part 310 is configured for moving the stopper of the syringe by movement of a plunger rod 314 which interacts with the stopper of the syringe. The operational module 306 comprises an optional drive axle 316 which is connected to the stopper operational part 310. The drive axle 316 provides that a driver, such as a DC motor, controls the stopper operational part 310 by operating the drive axle 316. Furthermore, the drive axle 316 provides control of the stopper operational part 310 independently of a location of the carrier 308.

The operational module 306 comprises a syringe operational part 312. The syringe operational part 312 is configured for moving the syringe. The syringe operational part 312 is configured for moving the syringe by moving the carrier 308 in a first syringe direction 522 and/or in a second syringe direction 524. The carrier 308 may be moved in order to mix a plurality of medicament components, such as a first medicament component and a second medicament component. Thus, the first syringe direction 522 may be a first mixing direction, and/or the second syringe direction 524 may be a second mixing direction. The syringe operational part 312 may further be configured for moving the syringe and/or the carrier 308 in the first syringe direction 522 to advance a needle of the syringe and/or a needle attached to the syringe, e.g. the syringe may be moved in the first syringe direction 522 for penetration of the skin and insertion of the needle into body tissue.

The syringe operational part 312 and the stopper operational part 310 may provide movements which are parallel, e.g. the stopper operational part 310 may provide movement of the plunger rod 314 in a direction parallel to the first syringe direction 522 and/or the second syringe direction 524. The first syringe direction 522 and/or the second syringe direction 524 may be along an axis, such as the tube axis of the syringe casing.

Fig. 14 schematically illustrates an exemplary system 400, 400', 400" comprising an auto injector 300 and a cartridge 200. The cartridge 200 comprises a syringe 100, 100' containing a medicament. The auto injector 300 is shown with outer parts, such as the housing, removed, to allow visibility of internal components of the auto injector 300. In the example illustrated, the cartridge 200 is received in the receiving part of the auto injector 300. The auto injector 300 comprises an operational module 306.

The operational module 306 comprises a stopper operational part 310 configured for moving a stopper of the syringe 100, 100', such as a first stopper of the syringe 100, 100'. For example, the first stopper of the syringe may be advanced to expel the medicament of the syringe, e.g. to inject the medicament into tissue of a patient, and/or the first stopper may be advanced to combine two or more medicament components, such as a first medicament component and a second medicament component.

The operational module 306 comprises a syringe operational part 312 configured for moving the syringe 100, 100'. For example, the syringe operational part 312 may be configured for advancing the needle 1 16, e.g. to insert the needle into tissue of a patient, and/or the syringe operational part 312 may be configured for moving the syringe 100, 100' back and forth in order to mix two or more medicament components, such as a first medicament component and a second medicament component, e.g. to dissolve a powder component in a liquid component.

The operational module 306 comprises a carrier 308. In the example depicted, the syringe 100, 100' is attached to the carrier 308, and the syringe operational part 312 is configured for moving the syringe 100, 100' by movement of the carrier 308. The syringe 100, 100' may be locked to the carrier 308 by a syringe lock (not shown), when the syringe 100, 100' is received in the receiving part of the auto injector 300. The syringe lock may have a locked state and an unlocked state, and the syringe lock may be configured to lock the syringe 100, 100' to the carrier 308 in the locked state.

The operational module 306 comprises one or more drivers, such as a stopper driver 380 and a syringe driver 382. The stopper driver 380 is configured to drive the stopper operational part 310, e.g. via a drive axle 316. The drive axle 316 provides that the stopper driver 380 may drive the stopper operational part 310 in all positions of the carrier 308. In an alternative embodiment, the stopper driver 380 may have been positioned on the carrier 308, reducing the need for a drive axle 316. The syringe driver 380 is configured to drive the syringe operational part 312, such as to move the carrier 308 and/or the syringe 100, 100'.

The stopper driver 380 and/or the syringe driver 382 may be DC motors, e.g. DC motors with or without brushes, e.g. the stopper driver 380 may be a brushed DC motor and/or the syringe driver 382 may be a brushless DC motor. A brushless DC motor may be preferred due to higher durability of a brushless DC motor. Especially for the syringe driver 382 a brushless DC motor may be preferred due to many and/or rapid movements performed by the syringe driver 382.

The auto injector 300 comprises sensors, such as an optical sensor 336. In the depicted example, the auto injector 300 comprises a plurality of optical sensors 336. The optical sensor(s) 336 may be configured for detecting medicament and/or blood in a channel, such as the needle chamber. The optical sensor(s) 336 may be configured for reading an optical code of the cartridge 200, such as an information code of the cartridge 200. A plurality of optical sensors 336, as shown, may provide the possibility of optical reading and/or detection for different positions of the syringe 100, 100'.

The auto injector 300 comprises a power unit 376, such as a battery, such as a rechargeable battery, such as a lithium-ion battery. The power unit 376 may supply power to electronic components of the auto injector, e.g. the stopper driver 380, the syringe driver 382, a processing unit, a memory, sensors, such as the optical sensor(s) 336, a user interface, etc.

The auto injector 300 comprises a contact switch 378. The contact switch 378 may provide a signal indicative of the cartridge 200 being inserted in the auto injector 300, e.g. of the cartridge 200 being received in the receiving part of the auto injector 300. Additionally or alternatively, the contact switch 378 may provide a signal indicative of the cartridge 200 and/or the syringe 100, 100' being pressed against a user's skin, e.g. a patient's skin. Thus, the contact switch 378 may be a skin sensor.

The cartridge 200 comprises a cover element 24. The cover element 24 is movable between a first position, as illustrated, and a second position. In the second position, the cover element covers at least a portion of the front end opening, and thereby reduces the front end opening, in order to provide protection of the needle 1 16, when the syringe 100, 100' is retracted, such that the needle 1 16 is enclosed inside the cartridge 200.

The cartridge 200 comprises a removable sheet 20. The removable sheet 20 covers the front surface and is configured for removal before abutment of the front end to a user's skin, e.g. a patient's skin. The removable sheet 20 may ensure that a front surface of the front end is maintained sterile until removal of the removable sheet 20, thereby reducing the risk of infection, e.g. infection carried from an operator of the device to the patient. Although particular features have been shown and described, it will be understood that they are not intended to limit the claimed invention, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the claimed invention. The specification and drawings are, accordingly to be regarded in an illustrative rather than restrictive sense. The claimed invention is intended to cover all alternatives, modifications and equivalents.

Embodiments and aspects are disclosed in the following items:

Item 1 . A cartridge for an auto injector, the cartridge comprising a syringe, the syringe comprising a compartment configured for containing a medicament, the syringe having a first syringe end and a second syringe end, the syringe having a syringe opening for fluid communication with the compartment at the first syringe end, the syringe comprising a first stopper movable inside the compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end, the syringe being configured to expel medicament through the syringe opening,

wherein the first stopper is configured for being locked to a plunger rod of the auto injector by a plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

Item 2. Cartridge according to any of the preceding items, wherein, when the plunger lock is in the locked state, the first stopper is movable in the second stopper direction by movement of the plunger rod in the second stopper direction.

Item 3. Cartridge according to any of the preceding items, wherein the plunger lock comprises at least a first locking member, the first locking member being configured to be movable between a first primary position and a first secondary position.

Item 4. Cartridge according to item 3, wherein, when the plunger lock is in the unlocked state, the first locking member is in the first primary position, and wherein when the plunger lock is in the locked state, the first locking member is in the first secondary position.

Item 5. Cartridge according to any of items 3 or 4, wherein the first locking member is in the first primary position when the first stopper is in a first stopper position, and the first locking member is in the first secondary position when the first stopper is in a second stopper position. Item 6. Cartridge according to item 5 wherein the second stopper position is positioned at a first distance from the first stopper position in the first stopper direction.

Item 7. Cartridge according to item 6, wherein the first distance is less than 6 mm.

Item 8. Cartridge according to any of items 3-7, wherein the first locking member is a latch arm, such as a flexible latch arm, or a latch arm comprising a flexible section, or a latch arm being flexibly connected to a plunger lock base of the plunger lock.

Item 9. Cartridge according to any of items 3-8, wherein the compartment has an inner compartment wall, and wherein the first locking member is brought into the first secondary position by contact with the inner compartment wall.

Item 10. Cartridge according to any of items 3-9, wherein the first locking member is biased towards the first primary position.

Item 1 1 . Cartridge according to any of the preceding items, wherein the plunger lock has a locking part with a first locking part diameter along a transverse stopper axis perpendicular to the stopper axis when the plunger lock is in the unlocked state and a second locking part diameter along the transverse stopper axis when the plunger lock is in the locked state, wherein the first locking part diameter is larger than the second locking part diameter.

Item 12. Cartridge according to any of the preceding items, wherein the plunger lock has a plunger lock receiving part with a plunger lock receiving part diameter along a transverse stopper axis perpendicular to the stopper axis, and the compartment has an inner compartment diameter along the transverse stopper axis, wherein the difference between the plunger lock receiving part diameter and the inner compartment diameter is larger than a diameter threshold.

Item 13. Cartridge according to any of the preceding items, wherein the plunger lock is attached to the first stopper.

Item 14. Cartridge according to any of items 1 -12, wherein the first stopper has a first primary stopper part with a first primary stopper diameter along a transverse stopper axis perpendicular to the stopper axis and a first secondary stopper part with a first secondary stopper diameter along the transverse stopper axis, wherein the first primary stopper part diameter is larger than the first secondary stopper part diameter.

Item 15. Cartridge according to item 14, wherein the first secondary stopper part is located between the first primary stopper part and the first syringe end. Item 16. Cartridge according to any of the preceding items, wherein the cartridge comprises a syringe casing comprising a main body being configured for receiving the syringe.

Item 17. Cartridge according to any of the preceding items, wherein the medicament comprises a poorly soluble medicament component.

Item 18. An auto injector for administering injection of a medicament, the auto injector comprising:

a housing;

a receiving part configured for receiving a cartridge comprising a syringe containing the medicament;

an operational module configured for interacting with the cartridge, the operational module comprising a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end, the first plunger rod end being proximal to the syringe when the cartridge is received in the receiving part, the operational module being configured for moving a first stopper of the syringe at least in a first stopper direction by movement of the plunger rod in the first stopper direction, and the plunger rod being configured for being locked to the first stopper by a plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

Item 19. Auto injector according to item 18, wherein, when the plunger rod is locked to the first stopper by the plunger lock, the operational module is configured for moving the first stopper of the syringe in a second stopper direction by movement of the plunger rod in the second stopper direction, wherein the second stopper direction is opposite the first stopper direction.

Item 20. Auto injector according to any of items 18-19, wherein the plunger lock is attached to the first stopper.

Item 21 . Auto injector according to any of items 18-19, wherein the plunger lock is attached to the plunger rod.

Item 22. Auto injector according to any of items 18-19, wherein the plunger rod has a first plunger rod part with a first plunger rod diameter along a transverse plunger rod axis perpendicular to the plunger rod axis and a second plunger rod part with a second plunger rod diameter along the transverse plunger rod axis, wherein the first plunger rod diameter is larger than the second plunger rod diameter. Item 23. Auto injector according to item 22, wherein the second plunger rod part is located between the first plunger rod part and the second plunger rod end.

Item 24. Auto injector according to any of items 18-23, wherein the operational module comprises a syringe lock having a locked state and an unlocked state and wherein the syringe lock is configured to lock the syringe to a carrier of the operational module in the locked state.

Item 25. Auto injector according to item 24, wherein the syringe lock comprises a first syringe locking member, the first syringe locking member being in a first position when the syringe lock is in the locked state, and the first syringe locking member being in a second position when the syringe lock is in the unlocked state.

Item 26. Auto injector according to item 25, wherein the first syringe locking member is biased towards the first position.

Item 27. Auto injector according to item 25 or 26, wherein the plunger rod is configured to force the first syringe locking member to the second position by a predefined movement in the second stopper direction.

Item 28. A system comprising an auto injector and a cartridge comprising a syringe containing a medicament;

the auto injector comprising:

a housing;

- a receiving part configured for receiving the cartridge;

an operational module configured for interacting with the cartridge, the operational module comprising a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end,

the cartridge comprising:

- the syringe comprising a compartment configured for containing the medicament, the syringe having a first syringe end and a second syringe end, the syringe having a syringe opening for fluid communication with the compartment at the first syringe end, the syringe comprising a first stopper movable inside the

compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end, the syringe being configured to expel medicament through the syringe opening, wherein the operational module is configured for moving the first stopper at least in the first stopper direction by movement of the plunger rod in the first stopper direction, and wherein the system comprises a plunger lock, the plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

Item 29. System according to item 28, wherein, when the plunger rod is locked to the first stopper by the plunger lock, the operational module is configured for moving the first stopper of the syringe in the second stopper direction by movement of the plunger rod in the second stopper direction.

Item 30. System according to any of items 28 or 29, wherein the plunger rod is locked to the first stopper by the plunger lock when the first stopper is in a second stopper position, and wherein the plunger rod is released from the plunger lock when the first stopper is in a first stopper position.

Item 31 . System according to item 30, wherein the second stopper position is positioned at a first distance from the first stopper position in the first stopper direction.

Item 32. System according to item 31 , wherein the first distance is less than 6 mm.

Item 33. System according to any of items 28-32, wherein the plunger lock comprises at least a first locking member, the first locking member being configured to be movable between a first primary position and a first secondary position.

Item 34. System according to item 33, wherein, when the plunger lock is in the unlocked state, the first locking member is in the first primary position, and wherein when the plunger lock is in the locked state, the first locking member is in the first secondary position.

Item 35. System according to any of items 33 or 34, wherein the first locking member is in the first primary position when the first stopper is in a first stopper position, and the first locking member is in the first secondary position when the first stopper is in a second stopper position.

Item 36. System according to any of items 33-35, wherein the first locking member is a latch arm, such as a flexible latch arm, or a latch arm comprising a flexible section, or a latch arm being flexibly connected to a plunger lock base of the plunger lock.

Item 37. System according to any of items 33-36, wherein the compartment has an inner compartment wall, and wherein the first locking member is brought into the first secondary position by contact with the inner compartment wall. Item 38. System according to any of items 33-37, wherein the first locking member is biased towards the first primary position.

Item 39. System according to any of items 28-38, wherein the plunger lock has a locking part with a first locking part diameter along a transverse stopper axis perpendicular to the stopper axis when the plunger lock is in the unlocked state and a second locking part diameter along the transverse stopper axis when the plunger lock is in the locked state, wherein the first locking part diameter is larger than the second locking part diameter.

Item 40. System according to any of items 28-39, wherein the plunger lock has a plunger lock receiving part with a plunger lock receiving part diameter along a transverse stopper axis perpendicular to the stopper axis, and the compartment has an inner compartment diameter along the transverse stopper axis, wherein the difference between the plunger lock receiving part diameter and the inner compartment diameter is larger than a diameter threshold.

Item 41 . System according to any of items 28-40, wherein the plunger lock is connected to the first stopper.

Item 42. System according to any of items 28-40, wherein the plunger lock is connected to the plunger rod.

Item 43. A plunger lock for a system comprising a plunger rod and a syringe containing a medicament, the plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to a first stopper of the syringe in the locked state.

LIST OF REFERENCES

2 syringe casing

4 main body

6 tube part

8 tube part outer perimeter

10 front end

12 front end opening

14 front end outer perimeter

16 inner body

18 locking element

20 removable sheet

22 front surface

24 cover element

26 cover part

28 cover opening

40 cover surface

100, 100' syringe

102 compartment

104 first syringe end

106 second syringe end

108 syringe opening

110 first syringe channel

1 12, 1 12' first stopper

1 14 second stopper

1 15 third stopper

1 16 needle

1 17 needle protective cover 1 18 inner compartment wall

120 outer compartment wall

122 inner compartment diameter

124 needle tip

126 medicament

128 first medicament component

130 second medicament component

134 first compartment part

136 second compartment part

138 middle bypass section

139 front bypass section

140 syringe cap

142 first primary stopper part

144 first secondary stopper part

146 first primary stopper part diameter

148 first secondary stopper part diameter

150 first syringe lock receiver

152 second syringe lock receiver

200 cartridge

202 plunger lock

203 plunger lock base

204 first locking member

206 second locking member

208 locking part

210 plunger lock receiving part

212 first locking part diameter

213 second locking part diameter 214 plunger lock receiving part diameter

216 first locking part outer diameter

218 second locking part outer diameter

220 first primary thickness

222 first secondary thickness

300 auto injector

302 housing

304 receiving part

306 operational module

308 carrier

310 stopper operational part

312 syringe operational part

314 plunger rod

316 drive axle

318 first plunger rod part

320 second plunger rod part

324 first plunger rod diameter

326 second plunger rod diameter

330 processing unit

336 optical sensor

350 display unit

354 housing front part

356 housing front part outer perimeter

358 user interface

366 syringe lock

368 first syringe locking member

370 second syringe locking member 372 first syringe locking member spring

374 second syringe locking member spring

376 power unit

378 contact switch

380 stopper driver

382 syringe driver

400, 400', 400" system

500 tube axis

502, 504, 505 first stopper direction

503 second stopper direction

512 stopper axis

516 plunger rod axis

522 first syringe direction

524 second syringe direction

530 syringe axis

Claims

1 . A cartridge for an auto injector, the cartridge comprising a syringe, the syringe comprising a compartment configured for containing a medicament, the syringe having a first syringe end and a second syringe end, the syringe having a syringe opening for fluid communication with the compartment at the first syringe end, the syringe comprising a first stopper movable inside the compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end, the syringe being configured to expel medicament through the syringe opening,

2. Cartridge according to any of the preceding claims, wherein, when the plunger lock is in the locked state, the first stopper is movable in the second stopper direction by movement of the plunger rod in the second stopper direction.

3. Cartridge according to any of the preceding claims, wherein the plunger lock comprises at least a first locking member, the first locking member being configured to be movable between a first primary position and a first secondary position, wherein, when the plunger lock is in the unlocked state, the first locking member is in the first primary position, and wherein when the plunger lock is in the locked state, the first locking member is in the first secondary position.

4. Cartridge according to claim 3, wherein the first locking member is in the first primary position when the first stopper is in a first stopper position, and the first locking member is in the first secondary position when the first stopper is in a second stopper position, wherein the second stopper position is positioned at a first distance from the first stopper position in the first stopper direction.

5. Cartridge according to any of claims 3 or 4, wherein the compartment has an inner compartment wall, and wherein the first locking member is brought into the first secondary position by contact with the inner compartment wall.

6. Cartridge according to any of claims 3-5, wherein the first locking member is biased towards the first primary position.

7. Cartridge according to any of the preceding claims, wherein the plunger lock has a locking part with a first locking part diameter along a transverse stopper axis perpendicular to the stopper axis when the plunger lock is in the unlocked state and a second locking part diameter along the transverse stopper axis when the plunger lock is in the locked state, wherein the first locking part diameter is larger than the second locking part diameter.

8. Cartridge according to any of the preceding claims, wherein the plunger lock has a plunger lock receiving part with a plunger lock receiving part diameter along a transverse stopper axis perpendicular to the stopper axis, and the compartment has an inner compartment diameter along the transverse stopper axis, wherein the difference between the plunger lock receiving part diameter and the inner compartment diameter is larger than a diameter threshold.

9. Cartridge according to any of the preceding claims, wherein the plunger lock is attached to the first stopper.

10. An auto injector for administering injection of a medicament, the auto injector comprising:

- a housing;

- a receiving part configured for receiving a cartridge comprising a syringe containing the medicament;

- an operational module configured for interacting with the cartridge, the operational module comprising a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end, the first plunger rod end being proximal to the syringe when the cartridge is received in the receiving part, the operational module being configured for moving a first stopper of the syringe at least in a first stopper direction by movement of the plunger rod in the first stopper direction, and the plunger rod being configured for being locked to the first stopper by a plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

1 1 . Auto injector according to claim 10, wherein, when the plunger rod is locked to the first stopper by the plunger lock, the operational module is configured for moving the first stopper of the syringe in a second stopper direction by movement of the plunger rod in the second stopper direction, wherein the second stopper direction is opposite the first stopper direction.

12. Auto injector according to any of claims 10 or 1 1 , wherein the plunger rod has a first plunger rod part with a first plunger rod diameter along a transverse plunger rod axis perpendicular to the plunger rod axis and a second plunger rod part with a second plunger rod diameter along the transverse plunger rod axis, wherein the first plunger rod diameter is larger than the second plunger rod diameter, and wherein the second plunger rod part is located between the first plunger rod part and the second plunger rod end.

13. Auto injector according to any of claims 10-12, wherein the operational module comprises a syringe lock having a locked state and an unlocked state and wherein the syringe lock is configured to lock the syringe to a carrier of the operational module in the locked state.

14. A system comprising an auto injector and a cartridge comprising a syringe containing a medicament;

the auto injector comprising:

- a housing;

- a receiving part configured for receiving the cartridge;

- an operational module configured for interacting with the cartridge, the operational module comprising a plunger rod extending along a plunger rod axis from a first plunger rod end to a second plunger rod end, the cartridge comprising:

- the syringe comprising a compartment configured for containing the

medicament, the syringe having a first syringe end and a second syringe end, the syringe having a syringe opening for fluid communication with the compartment at the first syringe end, the syringe comprising a first stopper movable inside the compartment along a stopper axis in a first stopper direction towards the first syringe end and in a second stopper direction towards the second syringe end, the syringe being configured to expel medicament through the syringe opening,

wherein the operational module is configured for moving the first stopper at least in the first stopper direction by movement of the plunger rod in the first stopper direction, and wherein the system comprises a plunger lock, the plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to the first stopper in the locked state.

15. System according to claim 14, wherein the plunger lock is connected to the first stopper.

16. System according to any of claims 14 or 16, wherein the plunger lock is connected to the plunger rod.

17. A plunger lock for a system comprising a plunger rod and a syringe containing a medicament, the plunger lock having a locked state and an unlocked state and being configured to lock the plunger rod to a first stopper of the syringe in the locked state.