Patent Application
20180110925
The present invention relates to autoinjectors and in particular to an autoinjector having separate parts allowing it to be worn by a user.
Ingesting, inhaling, and/or injecting certain allergens, toxins, and/or other substances can cause profound reactions for at least some and/or all people and/or animals. For example, certain people are highly allergic to certain substances, such as peanuts, shellfish, particular drugs, certain proteins, bee venom, insect bites, etc. The allergic response can lead to anaphylactic shock, which can cause a sharp drop in blood pressure, hives, and/or substantial breathing difficulties caused by severe airway constriction. As another example, inhalation of certain nerve agents can cause severe physiological trauma. Responding rapidly to such exposures can prevent injury and/or death. For example, in response to an exposure leading to anaphylactic shock, an injection of epinephrine (i.e., adrenaline) can provide substantial and/or complete relief from the reaction. As another example, injection of an antidote to a nerve agent can greatly reduce and/or eliminate the potential harm of the exposure. As yet another example, rapid injection of certain drugs, such as a beta blocker, blood thinner, nitroglycerine, antihistamines, insulin, and opioids, etc., can provide substantial relief from various dangerous medical conditions.
An autoinjector is a medical device designed to deliver one or more doses of a particular drug in a manner that facilitates self-administration of the drug via a syringe. By design, autoinjectors are easy to use and are intended to be used by patients or by untrained personnel. They typically are self-contained and designed to require only a few basic steps to operate.
It is a challenge to package components into a form factor that allows a user to wear a medical device. The medical device can include a syringe, a drug dose, and a source of stored energy needed to auto-inject the dose into the user. A solution to the challenge is a wearable drug delivery device having two separate parts, cases or housings. One part of the device can house the syringe and the drug dose, and this first part can be called the drug delivery pack. The second part of the device can house the stored energy source, and this second part can be called the power pack. The two packs can be coupled together in such a way that the energy released from the stored energy source in the power pack is conveyed to the drug delivery pack and used to move the drug dose through the syringe and into the user via the syringe.
An exemplary wearable drug delivery device includes a stored energy source disposed within a first housing. This device further includes a second housing comprising a syringe movable within the second housing between a withdrawn position and an extended position. The syringe includes a needle and a drug container in fluid communication with each other. The drug container can be filled with a dose of epinephrine or insulin. This device further includes a flexible conductor connected between the first housing and the second housing. The flexible conductor is configured to convey energy released from the stored energy source which moves the syringe to the extended position and extends the needle beyond the second housing.
The stored energy source can be a spring and the flexible conductor can be a Bowden cable.
The stored energy source can be a compressed gas and the flexible conductor can be a lumen.
The wearable drug delivery device can further include a release mechanism coupled to the stored energy source and configured to discharge stored energy. A trigger mechanism can be disposed at one end of the second housing and coupled to the release mechanism such that, in response to the trigger mechanism being activated, the release mechanism discharges the stored energy.
The wearable drug delivery device can further includes a release mechanism coupled to the stored energy source and configured to release stored energy. A trigger mechanism can be disposed at one end of the first housing and coupled to the release mechanism such that in response to the trigger mechanism being activated, the release mechanism discharges the stored energy.
The first housing can further include a first concave surface and the second housing can further include a second concave surface opposite the first concave surface. Each of the first and second concave surfaces extends along a longitudinal axis lying between the first housing and the second housing. Each of the first and second concave surfaces has a concavity defined by a point along the longitudinal axis. The first and second concave surfaces can be configured to conform to the human wrist.
The wearable drug delivery device can further include a cover hingedly attached to the first housing and operable between an initial close position and final open position. An interlock can be in releaseable engagement with the cover. When the interlock in unlocked, the cover swings from initial close position to the final open position. The interlock can include a recess defined by the first housing and a projection extending from the second housing. The interlock unlocks when the projection is inserted into the recess.
The second housing can include an open end through which the needle extends when the syringe is in the extended position. The wearable drug delivery device can further include a seal at the open end for keeping the needle sterile when the syringe is in the withdrawn position.
Another exemplary wearable drug delivery device includes a first housing including a first longitudinal axis and a first concave surface extending in the direction of the first longitudinal axis. The concavity of the first concave surface is defined by a point along an axis offset and parallel to the first longitudinal axis. The first housing further includes a stored energy source is disposed within the first housing. This device further includes a first connector disposed at an end of the first housing. The device further includes a second housing having a second longitudinal axis. The second housing includes a second concave surface extending in the direction of the second longitudinal axis. The concavity of the second concave surface is defined by a second point along an axis offset and parallel to the second longitudinal axis. The second housing includes a syringe that is movable within the second housing between a withdrawn position and an extended position. The syringe includes a needle and a drug container in fluid communication with each other. The drug container can be filled with a dose of epinephrine or insulin. The device further includes a second connector disposed at an end of the second housing. The second connector is adapted to couple the first connector of the first housing. The device further includes a band releasably coupled to the first housing and the second housing. When coupled to the band, the first concave surface of the first housing and the second concave surface of the second housing are opposite each other.
The stored energy source can be any one of a pre-compressed spring or compressed gas.
The first connector and the second connecting can be coaxially aligned with the first longitudinal axis and the second longitudinal axis, respectively. The first connector can be a recess defined in the end of the first housing and the second connector can be a protrusion extending from the end of the second housing. The recess can include radial slots and the protrusion can include radial tabs corresponding to the radial slots.
The foregoing and other objects, features and advantages will be apparent from the following more particular description of the embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the embodiments.
Moving the trigger portion 145 towards the housing 140 (e.g., pressing the trigger portion 145 against the user's thigh) causes the syringe 150 to move downwardly with the needle 155 extending beyond the trigger portion 145. In a convenient example of the wearable drug delivery device 100, the drug delivery pack 105 is sealed to maintain sterility. In the example, the needle 155 pierces through a sterile seal. In other examples, the drug delivery pack 105 further includes a trigger guard (not shown) separating the housing 140 from the trigger portion 145. The trigger guard prevents the drug delivery pack 105 from being accidently triggered.
In one example, the spring 170 is a compression spring, i.e., the spring 170 operates under a compression load and its length shortens when the compression load is applied. The release mechanism maintains a compression load holding the spring 170 under compression. Activating the release mechanism removes the compression load from the spring 170 and releases the mechanical energy stored in the spring 170. In turn, the movable end moves in a direction away from the fixed end of the spring 170, which for ease of reference is called a “push.” The flexible conductor 115 then conveys the released mechanical energy to the drug delivery pack 105, as will be described in greater detail below.
In another example, the spring 170 is a tension spring, i.e., the spring 170 operates under a tension load and its length shortens when the tension load is applied. The release mechanism maintains a tension load holding the spring 170 under tension. Activating the release mechanism removes the tension load from the spring 170 and releases the mechanical energy stored in the compression spring. In turn, the movable end moves in a direction toward the fixed end of the spring 170, which for ease of reference is called a “pull.” The flexible conductor 115 then conveys the released mechanical energy to the drug delivery pack 105.
The hollow outer cable housing 175 is generally of composite construction, consisting of an inner lining, a longitudinally incompressible layer, such as a helical winding or a sheaf of steel wire, and a protective outer covering. The inner cable 180 may a solid wire or a wire rope made up of smaller individual strands. The flexible conductor 115 may be constructed to hold a shape that facilitates wearing the wearable drug delivery device 100 on the user's wrist or arm. For example, the flexible conductor 115 includes members, such as wire form springs, giving the flexible conductor 115 a desired shape and flexibility. In another example, the flexible conductor 115 is made from an elastomer that may or may not be reinforced with braids or coils. One example of the flexible conductor 115 is a Bowden cable.
The flexible conductor 115 can convey/transfer the energy released from the spring 170 to the syringe 150 in a number of different ways involving additional components. Example components include a bell crank, a lever, or other part(s) for changing the direction of the conveyed energy. Other examples include a rack and pinion, a gear, a linkage, etc.
Upon puncturing the compressed gas container 280, compressed gas escapes and flows from the power pack 210 to the drug delivery pack 205 through the flexible lumen 215. At the drug delivery pack 205, the flowing gas meets the actuator 265 and applies pressure causing the actuator 265 to move in the downward direction (i.e., from proximal to distal). In turn, the actuator 265 moves the syringe 245 in the downward direction causing the needle 250 to exit the drug delivery pack 205. The syringe 245 continues to move until a stop within the drug delivery pack housing 240 prevents further movement. At this point, the needle 250 extends a certain distance beyond the drug delivery pack housing 240. Additional downward movement by the actuator 265 causes the plunger 260 to move downwardly within the drug container 255, thereby expelling the drug dose from the drug container, through the needle 250, and into the user.
The interlock 295 includes a first part on the drug delivery pack 205 and a second part on the power pack 210 that are combined in order to unlock the interlock 295. In the example shown, the first part is a tab 310 extending from the drug delivery pack housing 240 and the second part is a slot 315 (best seen in
To use the wearable drug delivery device 400 to auto-inject a drug dose, in one example, the user takes off the wearable drug delivery device 400 and removes the drug delivery pack 405 and power pack 410 from the band 415. The user then connects the drug delivery pack 405 to the power pack 410, as will be described next.
Returning to
In a convenient example of the wearable drug delivery device, the drug delivery pack 405 has an open end opposite the protrusion 440. The open end is covered by a seal that keeps the needle 485 sterile when the syringe is in the withdrawn position. When the syringe is in the extended position, the needle 485 pierces through the seal and extends through the open end.
In the example shown, the power pack 410 further includes a housing 505 containing a driving pin 510 attached to a pre-compressed spring 515. The driving pin 510 is movable in the direction of the longitudinal axis 432 (shown in
The release of energy causes the driving pin 510 to move to the distal position within the power pack housing 505 with the leading end 520 extending through the rigid connection 450. Referring in combination with
In other examples of the wearable drug delivery device 400, the pre-compressed spring 515 is replaced with a container of compressed gas or other similar stored energy source. The principles previously described above apply to such examples.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing examples are therefore to be considered in all respects illustrative rather than limiting of the invention described herein. Also, the words comprise, include, and/or plural forms of each are open ended and include the listed parts and can include additional parts or steps that are not listed, and the term and/or is open ended and includes one or more of the listed parts or steps and combinations of the listed parts steps.
This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application Ser. No. 62/411,310 filed on Oct. 21, 2016 the entire disclosure of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62411310 | Oct 2016 | US |
