Patent Publication Number: US-11040183-B2

Title: Receptacle portion of transdermal drug delivery apparatus and methods

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/996,158, which was filed on Apr. 30, 2014, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     The present subject matter relates generally to an apparatus for delivering drug formulations to a patient through the skin utilizing a microneedle assembly. 
     BACKGROUND 
     Numerous apparatus have previously been developed for the transdermal delivery of drugs and other medicinal compounds utilizing microneedle assemblies. Microneedles have the advantage of causing less pain to the patient as compared to larger conventional needles. In addition, conventional subcutaneous (often intra-muscular) delivery of drugs via a needle acts to deliver large amounts of a drug at one time, thereby often creating a spike in the bioavailability of the drug. For drugs with certain metabolic profiles this is not a significant problem. However, many drugs benefit from having a steady state concentration in the patient&#39;s blood stream; a well-known example of such a drug is insulin. Transdermal drug delivery apparatus are technically capable of slowly administering drugs at a constant rate over an extended period of time. Alternatively, transdermal drug delivery apparatus may administer drugs at variable rates. Thus, transdermal drug delivery apparatus offer several advantages relative to conventional subcutaneous drug delivery methods. 
     There is a desire for at least a portion of a transdermal drug delivery apparatus that provides a new balance of properties. 
     SUMMARY 
     An aspect of this disclosure is the provision of a receptacle that may be suitable for use as a portion of a transdermal drug delivery apparatus for being engaged to skin of a user. The receptacle may include a housing for being fastened to the user, a force provider that is elastic, at least one deformable component, and a microneedle assembly movably mounted to the housing for moving inwardly and outwardly relative to the housing. The microneedle assembly being movably mounted to the housing may be comprised of both the force provider being positioned between the housing and the microneedle assembly for forcing the microneedle assembly outwardly relative to the housing and against the skin of the user, and the at least one deformable component being connected between the microneedle assembly and the housing. The at least one deformable component may be connected between the microneedle assembly and the housing for both allowing relative movement between the microneedle assembly and the housing, and at least partially restricting the microneedle assembly from falling away from the housing. 
     The receptacle may further include a least one arresting member positioned between the housing and the microneedle assembly for restricting any movement of at least tips of microneedles of the microneedle assembly into an interior of the housing. The at least one arresting member may be connected to and extend outwardly relative to the microneedle assembly for engaging an interior surface of the housing for restricting any movement of at least the tips of the microneedles into an interior of the housing. The at least one arresting member may be in the form of a at least one flange and/or one or more lobes extending serially around the microneedle assembly. 
     The force provider may comprise a spring positioned between the housing and the microneedle assembly for urging the microneedle assembly outwardly relative to the housing. The at least one deformable component may be at least one flexible component, such as an adhesive membrane connected between the microneedle assembly and the housing. The receptacle may further include a chamber at least partially defined between a backside of the microneedle assembly and a backing structure, for supplying fluid to needles of the microneedle assembly. In addition, the a cannula may be mounted to the backing structure and in fluid communication with the chamber. 
     In accordance with another aspect of this disclosure, a receptacle for being used as a portion of a transdermal drug delivery apparatus may include a housing, a support structure movably positioned in the housing, and a microneedle assembly mounted to the support structure. The support structure may have opposite ends, and inwardly oriented connector parts for connecting to another portion of the apparatus, wherein the connector parts may be proximate the first end of the support structure. The microneedle assembly may be proximate the second end of the support structure. The support structure may comprise a sleeve having a sidewall, and the connector parts may be snap-fit connector parts. The snap-fit connector parts may comprise a series of spaced apart, flexible tabs extending radially inwardly from the sidewall of the sleeve. 
     One aspect of this disclosure is the provision of a method for at least partially assembling a receptacle that may be used as a portion of a transdermal drug delivery apparatus. The method may include compressing a force provider between a housing and a support structure, and connecting at least one deformable component between the housing and the support structure. The at least one deformable member may be configured for simultaneously restricting expansion of the spring, and allowing relative movement between the housing and the support structure. A microneedle assembly may be mounted to the support structure for moving with the support structure relative to the housing. 
     The compressing of the force provider (e.g., spring) may be comprised of causing first relative movement between the housing and the support structure while the force provider is positioned between the housing and the support structure. The method may further include releasing at least one of the housing and the support structure, the force provider causing second relative movement between the housing and the support structure in response to the releasing, and the at least one deformable component arresting the second relative movement between the housing and the support structure. 
     The foregoing presents a simplified summary of some aspects of this disclosure in order to provide a basic understanding. The foregoing summary is not extensive and is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. The purpose of the foregoing summary is to present some concepts of this disclosure in a simplified form as a prelude to the more detailed description that is presented later. For example, other aspects will become apparent from the following. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following, reference is made to the accompanying drawings, which are not necessarily drawn to scale and may be schematic. The drawings are exemplary only, and should not be construed as limiting the inventions. 
         FIG. 1  is a pictorial view of a drug deliver apparatus in its preactivated configuration and including a retention ring, in accordance with a first embodiment of this disclosure. 
         FIG. 2  is a side elevation view of the drug delivery apparatus of  FIG. 1  in an activated configuration without the retention ring and a release paper backing, and with its microneedle assembly in a flush position, in accordance with the first embodiment. 
         FIG. 3  is like  FIG. 2 , except for being a top plan view. 
         FIG. 4  is a partially exploded pictorial view of the drug delivery apparatus of  FIG. 1  without the retention ring. 
         FIG. 5  is an isolated, side cross-sectional view of a receptacle subassembly of the drug delivery apparatus of  FIG. 1 . 
         FIG. 6  is a schematic pictorial, cross-sectional view of a portion of a support structure and microneedle assembly of the receptacle subassembly of  FIG. 5 . 
         FIG. 7  is an isolated, schematic, bottom pictorial view of a frame or bezel of the support structure of  FIG. 6 . 
         FIG. 8  is an isolated, top pictorial view of a cartridge subassembly of the drug delivery apparatus of  FIG. 1 . 
         FIG. 9  is a bottom pictorial view of the cartridge subassembly of  FIG. 8 . 
         FIG. 10  is a schematic, side cross-sectional view of the cartridge subassembly of  FIG. 8 . 
         FIG. 11  is an isolated, top pictorial view of a controller subassembly of the drug delivery apparatus of  FIG. 1 , wherein the controller subassembly is in its unactuated state. 
         FIG. 12  is a bottom pictorial view of the controller subassembly of  FIG. 11 . 
         FIG. 13  is a side cross-sectional view of the controller subassembly of  FIG. 11 . 
         FIG. 14  is an exploded pictorial view of the controller subassembly of  FIG. 11 . 
         FIG. 15  is a pictorial, side cross-sectional view of the drug delivery apparatus of  FIG. 1  in the preactivated configuration without the retention ring. 
         FIG. 16  is a schematic view like  FIG. 15 , except that the drug delivery apparatus is in an intermediate configuration between the preactivated and activated configurations. 
         FIG. 17  is a schematic view like  FIG. 15 , except that the drug delivery apparatus is shown in the activated configuration. 
         FIGS. 18 and 19  schematically illustrate a latching mechanism of the controller subassembly being opened in response to the drug delivery apparatus being in the activated configuration. 
         FIG. 20  is a schematic view like  FIG. 15 , except that the drug delivery apparatus is shown in its fully-activated or post-activated configuration. 
         FIGS. 21 and 22  are isolated pictorial views of opposite sides of a lower support structure of the drug delivery apparatus, in accordance with a second embodiment, or the like. 
         FIG. 23  is a pictorial, side cross-sectional view of the drug delivery apparatus in the preactivated configuration without the retention ring, in accordance with the second embodiment, or the like. 
         FIG. 24  is an enlarged view of a portion of  FIG. 23 . 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments are described below and illustrated in the accompanying drawings, in which like numerals refer to like parts throughout the several views. The embodiments described provide examples and should not be interpreted as limiting the scope of the inventions. Other embodiments, and modifications and improvements of the described embodiments, will occur to those skilled in the art, and all such other embodiments, modifications, and improvements are within the scope of the present invention. 
     In the following, a very brief and general initial discussion of a drug delivery apparatus  10  of a first embodiment is followed by more detailed discussions, such as more detailed discussions of the separate subassemblies of the apparatus  10 . Referring to  FIG. 1 , the apparatus  10  is shown in its preactivated configuration, and a retention device, which is shown for example as being in the form of a retention ring  12 , is mounted to the apparatus. The retention ring  12  is for restricting the apparatus  10  from being transitioned from the preactivated configuration shown, for example, in  FIG. 1 , to an activated configuration shown, for example, in  FIGS. 2 and 3 . 
     Referring to the partially exploded view of  FIG. 4 , the apparatus  10  may be characterized as including multiple main subassemblies that each may be self-contained. The main subassemblies may include a receptacle  14 , a cartridge  16  or other suitable container or reservoir for being movably mounted in the receptacle, and a mechanical controller  18  mounted to the cartridge. Optionally, the cartridge  16  and controller  18  may be characterized as together forming one of the main subassemblies. 
     A protective release paper backing  20  may cover an adhesive backing of at least one deformable membrane  22  ( FIGS. 2 and 15-17 ) that is mounted to respective surfaces of the receptacle  14 . After removing any protective backing  20 , or the like, and preferably (e.g., optionally) while the apparatus  10  is in its fully assembled configuration shown in  FIG. 1 , the receptacle  14  may be attached to a user&#39;s (e.g., patient&#39;s) skin by way of the adhesive-backed deformable membrane  22 . The deformable component or membrane  22  may be referred to as an adhesive fastener, or more generally a fastener, for fastening at least a frame or housing of the receptacle  14  to the skin of a user, as will be discussed in greater detail below. 
     The receptacle  14  of the first embodiment includes a microneedle assembly or array  24  ( FIGS. 5, 6 and 15-17 ) having microneedles for penetrating the user&#39;s skin, such as for providing a fluid that may be in the form of a liquid drug formulation into the user&#39;s skin. The microneedle assembly  24  may be more generally referred to as a device for engaging the skin of a patient or other user, and dispensing the drug formulation to the user&#39;s skin, such as by dispensing the drug formulation into the epidermis portion of the user&#39;s skin. In contrast to how the apparatus  10  is shown in  FIG. 2 , it is typical for at least the tips of the microneedles of the microneedle assembly  24  to be protruding outwardly through a lower opening of the receptacle  14 . As a more specific example, while the apparatus  10  is in its activated configuration and the microneedle array  24  is penetrating the user&#39;s skin, at least the tips of, or the entire lengths of, the microneedles are typically protruding outwardly through a lower opening of the receptacle  14 . 
     Very generally described, the cartridge  16  is in the form of or comprises at least one storage container or reservoir that typically fully contains the liquid drug formulation in a hermetically sealed state during at least the preactivated configuration of the apparatus  10 . In the preactivated configuration, the interior of the cartridge-like storage container  16  (e.g., reservoir) is out of fluid communication with the microneedle assembly  24 . In contrast, while the apparatus  10  is in the activated configuration, the interior of the storage container  16  is in fluid communication with the microneedle assembly  24 , as will be discussed in greater detail below. 
     With the apparatus  10  oriented as shown in  FIG. 1  and in the preactivated configuration, an activation device or pushing mechanism that may be in the form of a button-like outer end of a frame or housing  26  of the controller  18  extends outwardly through an opening of the receptacle  14 . The apparatus  10  transitions from the preactivated configuration to the activated configuration in response to the button-like end of the controller housing  26  being manually pushed inwardly relative to the receptacle  14 . In the first embodiment, the transition from the preactivated configuration to the activated configuration includes relative movement between respective subassemblies of the apparatus  10 . The button-like end of the controller housing  26  may be configured differently and/or replaced with any other suitable component, such as a pushing mechanism, for triggering the transition from the preactivated configuration to the activated configuration. As will be discussed in greater detail below, the controller&#39;s housing  26  may be referred to as a pushing mechanism, or more specifically a pushbutton, or the like, for actuating the apparatus  10 . 
     The receptacle  14 , cartridge  16  and controller  18  may be originally fabricated as components that are separate from one another, and then be respectively mounted to one another. For example, the controller  18  may be conveniently mounted to the cartridge  16  by way of at least one mechanical connection and/or any other suitable fastening technique. Similarly, the cartridge  16  may be conveniently mounted to the receptacle  14  by way of at least one mechanical connection and/or any other suitable fastening technique. Each of, a majority of, or at least some of the mechanical connections may be at least partially defined by connector parts for forming connections, and each or at least some of the connections may be snap-fit connections, wherein each snap-fit connection may comprise a flexible, resilient latch. One or more of the connections may be for releasably securing the apparatus  10  in the preactivated configuration. Also, connector parts of the apparatus  10  may be configured for arresting relative movement between features of the apparatus and securing the apparatus in the activated configuration, as will be discussed in greater detail below. 
     Referring primarily to  FIG. 5 , the receptacle  14  of the first embodiment includes a compound frame or housing having an outer frame or body  30  and an inner frame or body  32 . The outer body  30  of the receptacle&#39;s housing includes at least one sidewall  34  extending at least partially around an interior space. In the first embodiment, the at least one sidewall  34  is in the form of a single sidewall  34  configured in substantially frusto-conical shape, so that the interior space of the outer body  30  is substantially frusto-conical. An annular upper edge of the sidewall  34  extends around an upper opening  36  to the interior space of the outer body  30 . The lower edge of the sidewall  34  terminates as an outwardly extending annular attachment flange  38  and/or the attachment flange  38  extends outwardly from an annular lower edge of the sidewall  34 . The attachment flange  38  extends around a lower opening to the interior space of the outer body  30 . The flange  38  may be referred to as an attachment flange because the adhesive membrane  22  is typically associated with the attachment flange for attaching the apparatus  10  to the skin of a user, as will be discussed in greater detail below. 
     For ease of understanding in this detailed description section of this disclosure, positional frames of reference, such as “upper” and “lower,” are used and can be understood with reference to the orientation of the apparatus  10  or features thereof in the drawings. However, the present invention is not limited to the positional frames of reference used in this detailed description section of this disclosure because, for example, the apparatus  10  of the first embodiment is configured so that it may be used in both inverted and uninverted positions. 
     With continued reference to  FIG. 5 , the central axis of the outer body  30 , around which the frusto-conical sidewall  34  of the outer body extends, may serve as a frame of reference that may be used throughout this detailed description section of this disclosure for ease of understanding, wherein an axial direction extends along (e.g., parallel to) the outer body&#39;s central axis, and radial directions extend outwardly from (e.g., perpendicular to) the outer body&#39;s central axis. Further regarding the axial direction, inner and outer axial positions or directions may be established relative to the center of a respective feature, such as relative to the position halfway between the upper and lower openings of the outer body  30 . For example the button-like end of the controller housing  26  extends axially outwardly through the upper opening  36  of the housing of the receptacle  14 . As another example, a substantial portion of the outer body  30  is positioned radially outwardly from the inner body  32 . Whereas one or more frames of reference are established for use in this detailed description section of this disclosure for ease of understanding, the present invention may also be described and understood with reference to other suitable frames of reference, such that the present invention is not limited to the frames of reference used in this detailed description section of this disclosure. 
     Further regarding the frusto-conical shape of the sidewall  34  of the outer body  30  and the central axis of the outer body, numerous of the features of the apparatus  10  that are positioned in the interior space of the outer body may have a substantially annular shape and may be substantially coaxially arranged with the outer body. Alternatively, the outer body  30  and the features of the apparatus  10  that are positioned in the interior space of the outer body may be shaped differently. For example, the at least one sidewall  34  of the outer body  30  may be in the form of multiple sidewalls that collectively extend around the interior space of the outer body, wherein the sidewalls may respectively meet at corners, or the like. Accordingly, features of the apparatus  10  that are positioned in the interior space of the outer body  30  may alternatively have configurations having corners that generally correspond to the corners of the outer body. For example, for each sidewall of the sidewalls of this disclosure, the sidewall may be segmented so as to be in the form of multiple sidewalls that respectively meet a corners, or the like. Similarly, other features of this disclosure may be segmented or configured in any suitable manner. 
     As best understood with continued reference to  FIG. 5 , the inner body  32  of the compound housing of the receptacle  14  is positioned in the interior space defined by the compound housing&#39;s outer body  30 . In the first embodiment, the outer body  30  is constructed of a material that is more flexible (e.g., has a greater modulus of elasticity or a greater bending modulus) than the material of the inner body  32 , so that at least a portion of the outer body may flex relative to the inner body. The inner body  32  is mounted to the interior of the outer body  30  by way of one or more mechanical connections, adhesive material and/or any other suitable fastening technique. Where practicable and in accordance with one aspect of this disclosure, mechanical connections may be used instead of using adhesive materials. 
     The inner body  32  includes an annular seat flange  42  extending radially outwardly from an axially extending cylindrical sidewall  44  of the inner body. The outer body  30  includes a shoulder engaged in a crotch defined between the seat flange  42  and sidewall  44  of the inner body  32 . The upper end of the sidewall  44  is engaged in an interior annular recess in the outer body  30 , and the outer end of the seat flange  42  engages against the inner surface of the sidewall  34  of the outer body. Alternatively, the outer and inner bodies  30 ,  32  of the frame or housing of the receptacle  14  may be constructed of the same type of material and they may be integrally formed with one another. Notwithstanding, for ease of understanding in this detailed description section of this disclosure, the housing of the receptacle  14  may be designated by the numerals  30 ,  32 . At least the receptacle&#39;s frame or housing  30 ,  32  is for being fastened to a user of the apparatus  10 , as will be discussed in greater detail below. 
     The receptacle  14  of the first embodiment further includes a support or support assembly, and one or more flexible or deformable components. The deformable components may include the deformable membrane  22  and a force provider that may be in the form of or comprise at least one metal, coil compression spring  46 . In the first embodiment, the support assembly of the receptacle  14  includes a first, radially outer support structure  50  that is movably mounted in the housing  30 ,  32 , and the support assembly further includes a second, radially inner support structure  52  that is fixedly mounted to the outer support structure  50 . As an example, the support structures  50 ,  52  may be connected to one another by one or more snap-fit connections, wherein each snap-fit connection may comprise a flexible, resilient latch, as will be discussed in greater detail below. 
     The microneedle assembly  24  may be fixedly mounted to the inner support structure  52 . For ease of understanding in this detailed description section of this disclosure, the support assembly of the receptacle  14  may be designated by the numerals  50 ,  52 . In the first embodiment, the microneedle assembly  24  is movably mounted to the housing  30 ,  32  by way of the support assembly  50 ,  52 , deformable membrane  22  and spring  46 . The deformable membrane  22  and spring  46  may optionally be referred to as being parts of the support assembly  50 ,  52 . 
     The outer support structure  50  may include or be in the form of a sleeve  50  configured for reciprocative sliding within the housing  30 ,  32 . The sleeve  50  includes an annular seat flange  54  extending radially outwardly from the lower end of the main sidewall of the sleeve. At the upper end of the sleeve  50 , the annular inner corner may be rounded, so that it comprises an annular beveled surface  58 , or the like. 
     The sleeve  50  further includes a series of spaced apart, flexible tabs or latches  56  that extend radially inwardly from the main sidewall of the sleeve, wherein considered collectively this series extends annularly. A majority of, at least some of, or each of the tabs or latches  56  may include a protrusion at its free end, wherein the protrusion extends radially inwardly from the free end of the tab or latch. The tabs or latches  56  may be connector parts, or more specifically latch-like snap-fit connector parts, as will be discussed in greater detail below. Whereas the connector latches  56  of the sleeve  50  of the first embodiment may be integrally formed with the sleeve, these connector parts may alternatively be originally formed separately from the sleeve and they may be mounted to, or otherwise associated with, the receptacle  14  in any suitable manner. The latches  56  may be proximate a first end of the support structure or sleeve  50 , whereas the microneedle assembly  24  may be proximate a second end of the sleeve, as will be discussed in greater detail below 
     The spring  46  is typically a coil spring that extends around both the sidewall of the sleeve  50  and the sidewall of the inner body  32  of the compound housing  30 ,  32 . The opposite ends of the spring  46  are respectively engaged against surfaces of the seat flanges  42 ,  54 , so that the seat flanges  42 ,  54  serve as seats for the spring. The inner body  32  of the compound housing  30 ,  32  may be referred to as a support, seat and/or guide since, for example, the seat flange  42  of the inner body  32  may serve as a seat for the spring  46 . As another example, the radially outer surface of the lower portion of the sidewall of the inner body  32  may serve as a guide for guiding axial compression and expansion of the spring  46 . In addition, the radially inner surface of the inner body  32  may serve as a guide for guiding axial, sliding relative movement between the inner body and the sleeve  50 . 
     As will be discussed in greater detail below, the spring  46  may be referred to as a force provider for indirectly forcing the microneedle assembly  24  outwardly relative to the housing  30 ,  32  of the receptacle  14 . More generally, the receptacle  14  includes a force provider for forcing the microneedle assembly  24  outwardly relative to the housing  30 ,  32 . The force provider may include at least the spring  46 , one or more of the springs  46 , and/or one or more other suitable force providing features that may be in the form of elastic objects, as will be discussed in greater detail below. 
     The deformable membrane  22  may be referred to as an arresting device or retainer that is for restricting the spring  46  or any other suitable force provider from separating the receptacle&#39;s support assembly  50 ,  52  (and thus the microneedle assembly  24 ) from the receptacle&#39;s housing  30 ,  32 . In one embodiment, the spring  46  or other suitable force provider may be able to push the receptacle&#39;s support assembly  50 ,  52  (and thus the microneedle assembly  24 ) out of the receptacle&#39;s housing  30 ,  32  were in not for the arresting or retaining functions provided by the deformable membrane  22 . Alternatively or in addition, these arresting or retaining functions may be provided by one or more other features of the apparatus  10 . 
     As shown in  FIG. 5 , an annular channel member  60  is fixedly mounted to the lower end of the sleeve  50  for traveling with the sleeve. The channel member  60  includes a centrally open, annular attachment plate  62  and axially extending annular mounting and arresting flanges  64 ,  66 . The flanges  64 ,  66  extend inwardly respectively from the inner and outer peripheral edges of the attachment plate  62 . The upper edge of the mounting flange  64  may be fixedly mounted to the lower end of the sleeve  50  so that the mounting flange may function as a spacer, standoff, or the like, so that a gap is defined between the attachment plate  62  and the seat flange  54  of the sleeve  50 . Alternatively, the gap may be omitted or provided in any other suitable manner. 
     The flange  66  may be referred to as arresting flange(s), arresting lobe(s), or the like, because an annular, beveled upper surface of the at least one arresting flange  66 , or the like, may engage the inner surface of the sidewall  34  of the outer body  30  for restricting relative movement between the compound housing  30 ,  32  and the sleeve  50  in a first direction in response to predetermined compression of the outer spring  46 . More specifically, the arresting lobe(s), arresting flange  66 , or the like, and the sidewall  34  of the outer body  30  may be cooperatively configured for restricting the microneedle assembly  24  from being pushed too far into the interior of the receptacle subassembly  14  during use of the apparatus  10 , as will be discussed in greater detail below. 
     The plate  62  may be referred to as an attachment plate because the adhesive membrane  22  is typically attached to the attachment plate for at least partially attaching the apparatus  10  to the skin of a user, as will be discussed in greater detail below. The channel member  60  may be constructed of a material that is more flexible than the material of the sleeve  50 , as will be discussed in greater detail below. Alternatively, the sleeve  50  and channel member  60  may be constructed of the same type of material and/or be engaged and connected to one another in any other suitable manner, or they may be integrally formed with one another. Accordingly, the channel member  60  may be characterized as being part of the sleeve  50  and vice versa. 
     Referring also to  FIG. 6 , the inner support structure  52  includes a frame  70  and a backing structure  72 . As at least alluded to above, the backing structure  72  is typically fixedly connected to the sidewall of the sleeve  50  for traveling therewith, and the periphery of the microneedle assembly  24  is fixedly mounted to the backing structure. More specifically, the periphery of the microneedle assembly  24  is fixedly mounted between the frame  70  and backing structure for moving therewith. The microneedle assembly  24  may be mounted between the frame  70  and backing structure  72  by way of one or more mechanical connections such as an interference fit, adhesive material and/or any other suitable fastening technique, as will be discussed in greater detail below. 
     As examples, the microneedle assembly  24  may be configured as disclosed in one or more of WO 2012/020332 to Ross, WO 2011/070457 to Ross, WO 2011/135532 to Ross, U.S. 2011/0270221 to Ross, and U.S. 2013/0165861 to Ross, wherein each of these documents is incorporated herein by reference in its entirety. Generally, the microneedle assembly  24  of the apparatus  10  may have any suitable configuration known in the art for delivering a fluidic drug formulation into and/or through the user&#39;s skin, such as by being configured to include one or more microneedles  74  extending outwardly from a suitable substrate or support, wherein this substrate or support may be referred to as a support plate  76  in this detailed description section for ease of understanding and not for the purpose of limiting the scope of this disclosure. As shown in  FIG. 6 , the support plate  76  has a top surface  78  (e.g., backside) and a bottom surface  80 , and multiple microneedles  74  extend outwardly from the bottom surface  80 . The support plate  76  and microneedles  74  may generally be constructed from a rigid, semi-rigid or flexible sheet of material, such as a metal material, a ceramic material, a polymer (e.g., plastic) material and/or any other suitable material. For example, the support plate  76  and microneedles  74  may be formed from silicon by way of reactive-ion etching, or in any other suitable manner. 
     The support plate  76  typically defines one or more passageways, which may be referred to as apertures, extending between, and open at each of, the top and bottom surfaces  78 ,  80  for permitting the drug formulation to flow therebetween. For example, a single aperture may be defined in the support plate  76  at the location of each microneedle  74  to permit the drug formulation to be delivered from the top surface  78  to such microneedle  74 . However, in other embodiments, the support plate  76  may define any other suitable number of apertures positioned at and/or spaced apart from the location of each microneedle  74 . 
     Each microneedle  74  of the microneedle assembly  24  may include a base that extends downwardly from the bottom surface  80  and transitions to a piercing or needle-like shape (e.g., a conical or pyramidal shape or a cylindrical shape transitioning to a conical or pyramidal shape) having a tip that is distant from the bottom surface  80 . The tip of each microneedle  74  is disposed furthest away from the support plate  76  and may define the smallest dimension (e.g., diameter or cross-sectional width) of each microneedle  74 . Additionally, each microneedle  74  may generally define any suitable length between its base and its tip that is sufficient to allow the microneedles  74  to penetrate the stratum corneum and pass into the epidermis of a user. It may be desirable to limit the length of the microneedles  74  such that they do not penetrate through the inner surface of the epidermis and into the dermis, which may advantageously help minimize pain for the patient receiving the drug formulation. 
     In one embodiment, each microneedle  74  may have a length of less than about 1000 micrometers (um), such as less than about 800 um, or less than about 750 um, or less than about 500 um (e.g., a length ranging from about 200 um to about 400 um), or any other subranges therebetween. In one specific example, the microneedles  74  may have a length of about 290 um. The length of the microneedles  74  may vary depending on the location at which the apparatus  10  is being used on a user. For example, the length of the microneedles  74  for an apparatus to be used on a user&#39;s leg may differ substantially from the length of the microneedles  74  for an apparatus to be used on a user&#39;s arm. Each microneedle  74  may generally define any suitable aspect ratio (i.e., the length over a cross-sectional width dimension of each microneedle  74 ). In certain embodiments, the aspect ratio may be greater than 2, such as greater than 3 or greater than 4. In instances in which the cross-sectional width dimension (e.g., diameter) varies over the length of each microneedle  74 , the aspect ratio may be determined based on the average cross-sectional width dimension. 
     Each microneedle  74  may define one or more channels in fluid communication with the apertures defined in the support plate  76 . In general, the channels may be defined at any suitable location on and/or within each microneedle  74 . For example, the channels may be defined along an exterior surface of each microneedle  74 . As a more specific example, each channel may be an outwardly open flute defined by the exterior surface of, and extending along the length of, a microneedle  74 . Alternatively and/or in addition, the channels may be defined through the interior of the microneedles  74  such that each microneedle  74  forms a hollow shaft. Regardless, the channels may generally be configured to form a pathway that enables the drug formulation to flow from the top surface  78  of the support plate  76 , through the apertures and into the channels, at which point the drug formulation may be delivered into and/or through the user&#39;s skin. The channels may be configured to define any suitable cross-sectional shape. For example, in one embodiment, each channel may define a semi-circular or circular shape. In another embodiment, each channel may define a non-circular shape, such as a “v” shape or any other suitable cross-sectional shape. 
     The dimensions of the channels defined by the microneedles  74  may be specifically selected to induce a capillary flow of the drug formulation. The capillary pressure within a channel is inversely proportional to the cross-sectional dimension of the channel and directly proportional to the surface energy of the subject fluid, multiplied by the cosine of the contact angle of the fluid at the interface defined between the fluid and the channel. Thus, to facilitate capillary flow of the drug formulation through the microneedle assembly  24 , the cross-sectional width dimension of the channel(s) (e.g., the diameter of the channel) may be selectively controlled, with smaller dimensions generally resulting in higher capillary pressures. For example, in several embodiments, the cross-sectional width dimension of the channels may be selected so that, with regard to the width of each channel, the cross-sectional area of each channel ranges from about 1,000 square microns (um 2 ) to about 125,000 um 2 , such as from about 1,250 um 2  to about 60,000 um 2 , or from about 6,000 um 2  to about 20,000 um 2 , or any other subranges therebetween. 
     The microneedle assembly  24  may generally include any suitable number of microneedles  74  extending from its support plate  76 . For example, in one embodiment, the actual number of microneedles  74  included within the microneedle assembly  24  may range from about 10 microneedles per square centimeter (cm 2 ) to about 1,500 microneedles per cm 2 , such as from about 50 microneedles per cm 2  to about 1250 microneedles per cm 2 , or from about 100 microneedles per cm 2  to about 500 microneedles per cm 2 , or any other subranges therebetween. The microneedles  74  may generally be arranged on the support plate  76  in a variety of different patterns, and such patterns may be designed for any particular use. For example, in one embodiment, the microneedles  74  may be spaced apart in a uniform manner, such as in a rectangular or square grid or in concentric circles. In such an embodiment, the spacing of the microneedles  74  may generally depend on numerous factors, including, but not limited to, the length and width of the microneedles  74 , as well as the amount and type of drug formulation that is intended to be delivered through the microneedles  74 . 
     Each of the opposite sides of the microneedle assembly  24  may be covered by (e.g., the microneedle assembly may include) one or more membranes (e.g., polymeric films). For example, the microneedles  74  may be covered by one or more membranes that may optionally include nanotopography, as disclosed by at least one of the documents previously incorporated herein by reference. However, any embossing or nanotopography may be omitted. As another example, the top surface  78  of the support plate  76  may be covered with one or more rate control membranes or other suitable membrane(s). For example, a rate control membrane may be fabricated from permeable, semi-permeable or microporous materials that are known in the art to control the rate of flow of drug formulations. 
     As best understood with reference to  FIG. 6 , at least a portion of the microneedle assembly&#39;s support plate  76  may have a substantially rectangular periphery that is in the form of or includes a peripheral channel  82  that (considering the support plate in isolation) is downwardly open and may have an overall substantially rectangular shape, or any other suitable shape. Similarly, the backing structure  72  of the first embodiment may be tiered or step-shaped so as to include inner and outer channels  84 ,  86  that (considering the backing structure in isolation) are downwardly open and may have an overall rectangular shape, or any other suitable shape. 
     A substantially rectangular gasket  88  may be engaged in the inner channel  84  and engaged securely against the margin of the rate control membrane and/or other suitable membrane that forms or is positioned at the top surface  78  of the microneedle assembly  24 . These secure engagements associated with the gasket  88  may result at least partially from the frame  70  being fixedly mounted to the backing structure. More specifically, the frame  70  may be fixedly mounted between the peripheral channel  82  of the microneedle assembly  24  and the outer channel  86  of the backing structure  72 . The frame  70  may be mounted between the peripheral and outer channels  82 ,  86  by way of one or more mechanical connections such as an interference fit, a mounting frame and/or any other suitable fastening technique, as discussed in greater detail below. In the first embodiment, the microneedle assembly  24  is substantially fixedly connected to backing structure  72  of the support assembly of the receptacle  14  by way of the subject connections. 
     The frame  70  may be characterized as being a substantially rectangular bezel having substantially S-shaped cross-sections. The outer peripheral edge of the frame  70  may be mounted into the outer channel  86  by way of, for example, a press-fit, so that the outer peripheral edge of the frame is in compressing, opposing-face-to-face contact with a flange that is part of or otherwise associated with (e.g., partially defines) the outer channel, and the inner peripheral margin of the frame is in compressing, opposing-face-to-face contact with the bottom surface  80  of the support plate  76 . More specifically, the frame  70  engages against a surface of the peripheral channel  82  of the support plate. 
     Alternatively, the microneedle assembly  24  may be mounted to the backing structure  72 , sleeve  50  or housing  30 ,  32  in any suitable manner. For example, and as previously indicated, features of the apparatus  10  may be configured differently than shown in the drawings. As a more specific example, the frame  70 , channels  82 ,  84 ,  86 , gasket  88  and other rectangular features may be in any other suitable shapes. As another example, whereas the backing structure  72  is shown in the drawings as being a single, unitary part, it may be constructed of separate parts that are connected to one another in any suitable manner. As an additional example, the outer periphery of the frame  70  may be secured in the outer channel  86  through the use of one or more attachment or mounting features, as will be discussed in greater detail below. 
     In the embodiment shown in  FIG. 6 , a lower face  77  of the backing structure  72 , top surface  78  of the support plate  76 , gasket  88  and inner channel  84  are cooperatively configured so that a peripherally closed gap  90  is defined between a portion of the radially inner surface of the gasket  88 , a central portion of the lower face of the backing structure  72 , and the central portion of the rate control membrane and/or other suitable membrane that forms or is positioned at the top surface  78  of the microneedle assembly  24 . This peripherally closed gap  90  may be referred to as a plenum chamber  90  that is preferably hermetically sealed or closed, except for being open to the apertures that extend through the support plate  76  and a hole or supply passageway  91  ( FIGS. 5 and 24 ) extending through the backing structure  72 . 
     Referring back to  FIG. 5 , the receptacle  14  further includes at least one cannula  92  fixedly mounted to the backing structure  72  for moving therewith. For example, a lower portion of the cannula  92  may be fixedly mounted in the supply passageway extending through the backing structure  72  by way of one or more mechanical connections such as an interference fit, adhesive material and/or any other suitable fastening technique. The lower open end of the cannula  92  is in fluid communication with the plenum chamber  90  ( FIG. 6 ), and the upper open end of the cannula, which is typically sharply pointed, extends axially upwardly from the backing structure  72  for piercing a predetermined portion of the cartridge  16  ( FIGS. 4 and 8-10 ), as will be discussed in greater detail below. The cannula  92  may extend through a sealing gasket  94  housed in a cavity of the backing structure  72  and/or sealing of the plenum chamber  90  may be provided in any suitable manner. 
     With continued reference to  FIG. 5 , the deformable membrane  22  may be in the form of a patch of double-sided pressure-sensitive adhesive tape, wherein the tape comprises a polymeric film with a relatively permanent adhesive material on one side and a relatively releasable adhesive material on the opposite side. The adhesively-coated, deformable membrane patch  22  may be substantially in the shape of a disk with a centrally located round opening, wherein the microneedles  74  ( FIG. 6 ) protrude outwardly through the central opening of the disk-shaped patch. The relatively permanent adhesive material is for permanently connecting the radially inner marginal portion of the membrane patch  22  to the annular attachment plate  62 , and the relatively permanent adhesive material is for permanently connecting the radially outer marginal portion of the membrane patch  22  to the annular attachment flange  38 . Optionally, the channel member  60  may be omitted and the relatively permanent adhesive material may connect the radially inner marginal portion of the membrane patch  22  to the seat flange  54  of the sleeve  50  or to another suitable feature. Alternatively, the seat flange  54 , annular channel member  60  and/or portions thereof may be part of the inner or lower support structure  52 , as will be discussed in greater detail below. 
     The relatively releasable adhesive material is for releasably connecting the membrane patch  22  to the user&#39;s skin for the purpose of fastening the apparatus  10  to the user. For example, the adhesives may be selected from conventional adhesive materials, such as acrylic adhesive materials. As a more specific example, the relatively releasable adhesive material may be a silicon adhesive material having at least two relaxation modes, wherein the adhesive bond of the silicon adhesive material may be stronger in one mode than the other. For example, the silicon adhesive may have a lower adhesive strength when the membrane patch  22  is slowly separated from the user&#39;s skin, as compared to when the membrane patch  22  is quickly separated from the user&#39;s skin. The silicone adhesive may be or may comprise a silicone gel. In this manner, the membrane patch  22  can be readily removed from the skin by the wearer after use, while at the same time preventing the apparatus  10  from being inadvertently or prematurely disengaged from the skin, for example, by accidentally bumping or knocking the apparatus during use. 
     The protective backing  20  ( FIG. 1 ), which may be present for temporarily, removably covering the relatively releasable adhesive material of the membrane patch  22 , may be in the shape of disk with a centrally located round opening, and an outwardly protruding pull tab may protrude from the disk. The protective backing  20  may comprise a conventional paper-based material with a conventional release coating that is engaged against the relatively releasable adhesive material of the membrane patch  22 , or the protective backing may be in any other suitable configuration. 
     Referring to  FIGS. 8-10 , the receptacle or cartridge  16  ( FIG. 2 ) may include or be in the form of a storage container  16  for receiving and containing the drug formulation associated with the apparatus  10 . The cartridge-like storage container  16  of the first embodiment includes at least one body  96  defining relatively wide and relatively narrow cavities  98 ,  100  ( FIG. 10 ) that are open to one another, such as by way of a passageway defined in the body  96  and extending between and open to each of the wide and narrow cavities. In the first embodiment, the passageway defined in the body  96  is contiguous with both of the cavities  98 ,  100 . 
     As best understood with reference to  FIG. 10 , the wide cavity  98  is substantially concave or substantially bowl shaped, such that at least one surface of the body  96  that defines the wide cavity is concave in numerous cross-sections. That is, the wide cavity  98  may be at least partially defined by a substantially concave wall of the body  96 , and the substantially concave wall may more specifically be a substantially bowl-shaped wall. 
     As also best understood with reference to  FIG. 10 , the narrow cavity  100  includes a cylindrical section that tapers to a frustoconical section. As shown in  FIG. 10 , one end of the passageway connecting the cavities  98 ,  100  is open at the highest point of the tip of narrow cavity  100 , and the opposite end of the passageway connecting the cavities  98 ,  100  is open at the lowest point of the substantially bowl-shaped wide cavity  98 . That is, the respective end of the subject passageway may be open proximate, or more specifically at, the central portion of the substantially concave wall that at least partially defines the wide cavity  98 . Even more specifically, the respective end of the subject passageway may be open proximate, or more specifically at, the central portion of the substantially bowl-shaped wall that at least partially defines the wide cavity  98 . The cavities  98 ,  100  and associated passageway may be configured differently than discussed above. Nonetheless, for ease of understanding in this detailed description section of this disclosure, relative terms such as “narrow” and “wide” are used for identification purposes, even though the present invention is not limited so such terms or relative sizes. 
     The body  96  defines opposite outer openings that are respectively positioned at opposite ends of the body. These openings are open to and contiguous with the cavities  98 ,  100 , respectively. The outer opening to the wide cavity  98  is closed by a relatively wide closure  102 , and the outer opening to the narrow cavity  100  is closed by a relatively narrow closure  104 . The wide and narrow closures  102 ,  104  are respectively mounted proximate, or more specifically mounted to, the opposite ends of the body  96 . 
     The narrow closure  104  includes a cap  106 , or the like, securing a self-sealing member over the outer opening to the narrow cavity  100 . The self-sealing member may be a disk-shaped self-sealing septum  108  or any other suitable self-sealing member. The cap  106  secures the self-sealing septum  108  over the outer opening to the narrow cavity  100 , so that the self-sealing septum is in compressed, opposing-face-to-face contact with an end of a flange of the body  96  that defines the outer opening to the narrow cavity. In this configuration, the septum  108  at least partially closes, or more specifically completely closes, the outer opening to the narrow cavity  100 . 
     The cap  106  may generally include a disk  110 , or the like, with a centrally located opening for providing access to the self-sealing septum  108 . The cap  106  may further include an annular flange  112  extending axially from a peripheral edge of the disk  110 . The cap  106  may be mounted at least by the flange  112  of the cap  106  being engaged to and mounted to a corresponding flange of the body  96  by way of one or more mechanical connections such as an interference fit, adhesive material, a weld joint (e.g., spin welding, ultrasonic welding, laser welding or heat staking) and/or any other suitable fastening technique. The flange  112  may be described as being a cylindrical flange or a cylinder  112 , and the disk  110  may be referred to as an annular flange extending inwardly from an end edge of the cylinder  112 . 
     The wide closure  102  includes a cap  114 , or the like, securing a movable member over the outer opening to the wide cavity  98 . The movable member over the outer opening to the wide cavity  98  may be a disk-shaped deformable membrane  116 . The cap  114  may secure the disk-shaped member or deformable membrane  116  over the outer opening to the wide cavity  98  so that the deformable membrane  116  is in compressed, opposing-face-to-face contact with an end face of the body  96  that defines the outer opening to the wide cavity. In this configuration, the membrane  116  at least partially closes, or more specifically completely closes, the outer opening to the wide cavity  98 . 
     Generally described, the cap  114  may include a disk  118 , and inner and outer annular flanges  120 ,  122  extending axially in opposite directions from the disk. The disk  118  has a centrally located opening for providing access to the deformable membrane  116 . Referring to  FIG. 10 , the cap  114  may be mounted at least by the outer flange  122  of the cap  114  being engaged to and mounted to a corresponding flange  124  of the body  96 , such as by way of an annular flange  126  extending radially inwardly from an end of the outer flange  122  and engaging against an end edge of the flange  124  of the body. The inner and outer flanges  120 ,  122  may be described as being integrally formed coaxial inner and outer cylinders  120 ,  122 , wherein an annular shoulder  128  of the cap  114  may be defined at the transition between the inner and outer cylinders  120 ,  122  and/or flanges  120 ,  122 . Alternatively or additionally, the outer flange  122  of the cap  114  may be mounted to the flange  124  of the body  96 , by way of one or more mechanical connections such as an interference fit, adhesive material, a weld joint (e.g., spin welding, ultrasonic welding, laser welding or heat staking) and/or any other suitable fastening technique. 
     Referring initially to  FIG. 8 , the cap  114  or portions thereof may be referred to as structure for supporting and/or defining connector parts for at least partially forming mechanical connections that may be releasable. For example, some of the connector parts of the cap  114  may be in the form of a series of spaced apart, flange-like, arcuate protruding connector parts  130  extending radially outwardly from the inner cylinder or flange  120 . As another example, other of the connector parts of the cap  114  may be in the form of outwardly oriented or open, upper and lower annular groove connector parts  132 ,  134  that are defined by the outer cylinder or flange  122  and spaced apart from one another along the length of the cap  114 . Whereas the connector parts  130 ,  132 ,  134  of the cap  114  of the first embodiment may be integrally formed with the cap  114 , these connector parts may alternatively be originally formed separately from the cap  114  and they may be mounted to, or otherwise associated with, the cartridge  16  in any suitable manner. More generally, the connector parts  130 ,  132 ,  134  extend outwardly from the body  96  of the receptacle or cartridge  16 , and the connector parts  130 ,  132 ,  134  may be connected to or otherwise associated with the body  96  in any suitable manner. 
     Referring to  FIGS. 11-14 , and initially primarily to  FIG. 14 , the controller  18  includes the controller housing  26 ; an activation device or pushing mechanism that may be in the form of a plunger  140 , or the like; at least one force provider that may be in the form of or comprise at least one metal, coil compression spring  142  positioned between the controller housing and the plunger for moving the plunger relative to the controller housing; and a latching mechanism  144  for selectively restricting and allowing relative movement between the housing and the plunger. The controller  18  may also include a guide member or disk  146  and elastic ring  148 . 
     As will be discussed in greater detail below, the spring  142  may be referred to as a force provider for forcing the plunger  140  outwardly relative to the controller housing  26 . More generally, the controller  18  includes a force provider for forcing the plunger  140  outwardly relative to the controller housing  26 , wherein the force provider may comprise the spring  142 , one or more of the springs  142 , and/or one or more other suitable force providing features that may be in the form of elastic objects, as will be discussed in greater detail below. In the illustrated embodiment, the first force provider or spring  46  ( FIG. 5 ) is larger than, and may be stronger than, the second force provider or spring  142 , as will be discussed in greater detail below. 
     The controller housing  26  includes at least one wall, or more specifically a pair of spaced apart arcuate walls  150  extending axially from a terminal portion that may be in the form of a plate or disk  152 . The terminal portion or disk  152  may be generally or at least somewhat dome-shaped and may serve as a pushbutton or portion of a pushbutton for being manually pressed, as will be discussed in greater detail below. Similarly, the controller housing  26  as a whole, or portions thereof, may be referred to as a pushbutton, as will be discussed in greater detail below. Although the controller housing  26  and/or features thereof may be configured differently, for ease of understanding and not for purposes of narrowing the scope of the present invention, the controller housing  26  may be referred to as a button  26 , and the disk  152  may be referred to as a button plate or button disk  152  in this detailed description section of this disclosure. The arcuate walls  150  extend along, but are spaced apart inwardly from, the periphery of the button disk  152 , so that an annular shoulder  154  of the button disk extends radially outwardly from the arcuate walls  150 . A groove in the arcuate walls  150  defines arcuate shoulders  156  ( FIG. 12 ). 
     The arcuate walls  150  may each be referred to as a structure for supporting and/or defining connector parts for at least partially forming mechanical connections. For example, the connector parts of the arcuate walls  150  may be in the form of a series of spaced apart, flange-like, arcuate protruding connector parts  158  ( FIG. 12 ) extending radially inwardly from the arcuate walls  150 . Whereas the connector parts  158  of the controller housing  26  may be integrally formed with the controller housing  26 , these connector parts may alternatively be originally formed separately from the controller housing and they may be mounted to, or otherwise associated with, the controller  18  in any suitable manner. 
     The controller housing  26  includes a central protrusion, guide or guidepost  160  ( FIGS. 13 and 14 ) extending coaxially from the inner side of the button disk  152  for extending into, and guiding, the coil spring  142  and the plunger  140 . The plunger  140  includes a cylindrical shaft  162  ( FIG. 14 ) coaxially extending from a domed head  164 . Outwardly open, upper and lower recesses that may be in the form of annular grooves  166 ,  168  ( FIG. 13 ) are defined in the plunger&#39;s shaft  162 . The at least one wall  150  of the controller housing  26  extends at least partially around shaft  162 , which extends at least partially around the spring  142 , which extends at least partially around the guide or guidepost  160 . 
     Referring to  FIGS. 12 and 14 , the latching mechanism  144  has opposite ends that extend at least partially into, or more specifically at least partially through, the holes, slots or gaps between the arcuate walls  150 . Each end of the latch  144  includes an axially protruding, arcuate skirt portion  172 , and a radially outwardly protruding actuator or actuation tab having an arcuate beveled surface  170 . For each of the opposite ends of the latch  144 , the beveled actuating surface  170  and the skirt portion  172  each extend substantially all the way between the adjacent ends of the arcuate walls  150 , so that the ends of the latch obstruct, or more specifically substantially close, the holes, gaps or slots between adjacent ends of the arcuate walls  150 . 
     Referring to  FIGS. 14, 18 and 19 , the latch  144  further includes a pair of locking members, locking bars, or locking arms  174  that extend between the opposite ends of the latch. While the plunger  140  is in its retracted position, its shaft  162  extends through a space defined between middle portions of the locking arms  174 , and the middle portions of the locking arms extend into the upper groove  166  in the shaft  162  while the latch is in its locking or unactuated state. In this state, the locking arms  174  one or more shoulders of the shaft  162 , wherein these shoulders that at least partially define the upper annular groove  166 . Pairs of guide members or guide arms  176  may extend arcuately from proximate the opposite ends of the latch for respectively engaging the interior surfaces of the arcuate walls  150 . Whereas the latch  144  has been described as having features in pairs, the latch may be configured differently, such as by omitting one of each pair, or the like. 
     Referring to  FIG. 13 , the inner periphery of the guide disk  146  may be retained in the upper groove  168  in the shaft  162  of the plunger  140 . The elastic ring  148  may be positioned between, and in opposing face-to-face contact with each of, the guide disk  146  and the guide arms  176  of the latch  144 . The elastic ring  148  may engage the inner faces of the skirt portions  172  for helping to maintain the latch  144  in its unactuated state and/or the latch  144  may be made out of a elastic material that biases the latch toward its unactuated state. 
     The at least one arcuate wall  150  of the pushbutton or controller housing  26  extends at least partially around an interior space. At least a portion of each of the plunger  140 , spring  142 , latch  144 , guide disk  146 , elastic ring  148 , guidepost  160  and/or shaft  162  may be positioned in the interior space that the at least one arcuate wall  150  extends around. Substantially the entirety of each of the plunger  140 , spring  142 , latch  144 , guide disk  146 , elastic ring  148 , guidepost  160  and/or shaft  162  may be positioned in the interior space that the at least one arcuate wall  150  extends around. Other configurations of the controller  18  are also within the scope of this disclosure. 
     Whereas examples of some methods that may be associated with the apparatus  10  have been discussed above, others are discussed in the following, in accordance with the first embodiment. For example and referring back to  FIG. 5 , the microneedle assembly  24  may be substantially fixedly mounted to the support assembly  50 ,  52 , in the manner discussed above, either before or after the receptacle&#39;s support assembly  50 ,  52  is movably mounted to the receptacle&#39;s housing  30 ,  32 . The support assembly  50 ,  52  is movably mounted to the receptacle&#39;s housing  30 ,  32  so that the support assembly  50 ,  52 , and thus the microneedle assembly  24  carried by the support assembly  50 ,  52 , may be moved inwardly and outwardly relative to the housing  30 ,  32 . 
     With continued reference to  FIG. 5 , the support structure or support assembly  50 ,  52  may be movably mounted to the housing  30 ,  32  by compressing the respective force provider, which may comprise the spring  47 , between the support assembly  50 ,  52  and the housing  30 ,  32 , and then by connecting at least one deformable component, such as the deformable membrane  22 , between the support assembly  50 ,  52  and the housing  30 ,  32 . The deformable membrane  22  is for simultaneously restricting expansion of the spring  47  and allowing relative movement between the support assembly  50 ,  52  and the housing  30 ,  32 . For example, the at least the deformable membrane  22  may keep the support assembly  50 ,  52  and the spring  47  from falling away from, or more specifically out of, the housing  30 ,  32 . In this regard and reiterating from above, the deformable membrane  22  may be referred to as an arresting device or retainer that is for restricting the spring  46  or any other suitable force provider from separating the receptacle&#39;s support assembly  50 ,  52  (and thus the microneedle assembly  24 ) from the receptacle&#39;s housing  30 ,  32 . 
     Further regarding the mounting of the support structure or assembly  50 ,  52  to the housing  30 ,  32 , manual compressing of the spring  47  may be comprised of causing a first relative movement between the support assembly  50 ,  52  and the housing  30 ,  32 . After the deformable membrane  22  is installed, the support assembly  50 ,  52  and/or the housing  30 ,  32  may be manually released, so that the spring  47  causes a second relative movement between the support assembly  50 ,  52  and the housing  30 ,  32 . The second relative movement may be partially restricted by the deformable membrane  22  and/or any other suitable features. 
     Generally described, the controller  18  may be assembled by substantially coaxially arranging its features as shown in  FIG. 14 , and then respectively bringing the features into contact with one another as shown in  FIG. 13 . More specifically, the subject force provider, which may comprise the spring  142 , may be compressed between the pushbutton or controller housing  26  and the pushing mechanism or plunger  140 . This compressing may be achieved through relative movement between the controller housing  26  and plunger  140 . As part of this or other relative movement, the shaft  162  of the plunger  140  may be moved into and through a hole in the latching mechanism  144 . The subject hole in the latching mechanism  144  may be defined between the locking members or arms  174 . The shaft  162  may pass into the hole in the latching mechanism  144  by way of the shaft pushing the locking arms  174  apart and enlarging the hole, wherein the locking arms may elastically move into the groove  166  in the shaft  162  to arrest the subject relative movement and hold the plunger  140  in its retracted position. In this regard, the locking arms  174  more specifically engage against at least one shoulder of the shaft  162  for holding the plunger  140  in its retracted position, wherein the subject shoulder of the shaft partially defines the groove  166 . However, the subject shoulder(s) may be configured differently. 
     As best understood with reference to  FIG. 19 , the cartridge  16  and controller  18  being connected to one another and/or other features, such as the guide disk  146  and support ring  148 , are cooperative for restricting axial movement of the latching mechanism  144 . The cartridge  16  and controller  18  may be connected to one another as shown in  FIG. 2  by causing relative axial movement between the cartridge and controller so that the protruding connector parts  130  ( FIG. 8 ) of the cartridge pass through the spaces defined between the protruding connector parts  158  ( FIG. 12 ) of the controller, and vise versa. The relative axial movement may continue until the free edge of the inner flange  120  ( FIGS. 8 and 10 ) of the cartridge  16  and the guide disk  146  ( FIGS. 12-14 ) of the controller  18  engage against one another, and the shoulder  128  ( FIGS. 8 and 10 ) of the cap  114  and the lower edges of the arcuate walls  150  ( FIGS. 11-13 ) of the controller housing  26  engage against one another. Then, through relative rotation between the cartridge  16  and controller  18 , the protruding connector parts  130 ,  158  respectively engage behind one another, so that the cartridge and controller are mounted to one another by way of the protruding connector parts  130 ,  158 . Additionally or alternatively, the cartridge  16  and controller  18  may be mounted to one another by way of any other suitable mechanical connections and/or any other suitable fastening techniques. For example, the connector parts  130 ,  158  may be supplemented with or replaced by one or more weld joints that may be formed, for example, by spin welding, ultrasonic welding, laser welding, heat staking and/or any other suitable technique. As another example, the cartridge  16  and controller  18  may be connected to one another by one or more snap-fit connections, wherein each snap-fit connection may comprise a flexible, resilient latch, as will be discussed in greater detail below. 
     As best understood with reference to  FIG. 10 , preparing the apparatus  10  for use may include charging the reservoir or cartridge  16  with a drug formulation. The drug formulation may be injected through the self-sealing septum  108  into the narrow cavity  100 , so that the drug formulation also flows into the wide cavity  98  by way of the passageway between the narrow and wide cavities. For example, the drug formulation may be injected through the self-sealing septum  108  using conventional charging devices that are conventionally used to fill conventional vials with caps equipped with self-sealing septums. A charging device may include coaxial needles for extending through the self-sealing septum  108 , wherein one of the needles draws a partial vacuum in the cavities  98 ,  100  and the other needle injects the drug formulation. The drug formulation may substantially fill the interior of the cartridge  16  so that any air may be substantially eliminated from the interior of the cartridge. 
     The cartridge  16  may be charged with a drug formulation either before or after the cartridge  16  and controller  18  are mounted to one another. Irrespective, the cartridge  16  will typically be charged with a drug formulation under septic conditions. In one example, the interior volume of the reservoir or cartridge  16  may be up to about 500 μL, and the microneedle assembly  24  may be about 12.5 mm by about 12.5 mm. In another example, the interior volume of the reservoir or cartridge  16  may be up to about 2 mL, and the microneedle assembly  24  may be about 25 mm by about 25 mm. Other volumes and sizes are within the scope of this disclosure. For example, the volume the interior of the reservoir or cartridge  16  may be in a range of about 100 μL to about 2 mL or more. Those of ordinary skill in the art will understand how to make appropriate use of cleanrooms and sterilization in association with the apparatus  10 . 
     As best understood with reference to  FIG. 4 , the assembled together cartridge  16  and controller  18  may optionally be encircled by the retention ring  12  ( FIG. 12 ) and then be mounted into the receptacle  14  by introducing the lower end of the cartridge  16  into the upper opening  36  of the receptacle  14 . As may be understood with reference to  FIGS. 4, 5, 8 and 15 , there may be relative sliding between the protruding tips of the latch connector parts  56  ( FIGS. 4 and 5 ) and the outer housing or flange  122  ( FIGS. 8-10 ) of the cartridge  16 . The subject relative sliding may be in response to relative movement between the receptacle  14  and the cartridge  16  while the cartridge is at least partially positioned in the interior space surrounded by the sleeve  50  ( FIGS. 4 and 5 ), and this relative movement may be caused by manually pushing down on the button disk  152 . The cartridge  16  and controller  18  may have been previously mounted to one another as discussed above, so they move with one another in response to the button disk  152  being pushed. 
     The apparatus  10  is shown in its preactivated configuration in  FIGS. 1 and 15 , although the retention ring  12  is omitted from  FIG. 15 . When the cartridge  16  and the controller  18  are being initially installed in the receptacle  14 , the relative movement between the receptacle  14  and cartridge  16  may be automatically arrested when the preactivated configuration is reached. The relative movement between the receptacle  14  and cartridge  16  may be arrested in response to engagement of at least one obstruction for releasably securing the drug delivery apparatus in the preactivated configuration. The obstruction may comprise at least one releasable mechanical connection and/or at least one retention device. For example, the retention ring  12  ( FIG. 1 ) or any other suitable retention device may engage between the shoulder  154  ( FIGS. 12 and 13 ) of the button disk  152  and the upper edge of the sleeve  50  ( FIGS. 4 and 5 ) to arrest the relative movement when the apparatus  10  reaches the preactivated configuration. 
     In accordance with the first embodiment, the apparatus  10  is configured so that at substantially the same time that the retention ring  12 , or the like, engages between the shoulder  154  of the button disk  152  and the upper edge of the sleeve  50  to arrest the relative movement between the receptacle  14  and cartridge  16  when the apparatus reaches the preactivated configuration, the protruding tips of the latch connector parts  56  ( FIGS. 5 and 15 ) reach the lower groove connector part  134  ( FIGS. 8-10 ). When the protruding tips of the latch connector parts  56  reach the lower groove connector part  134 , the radially inwardly biased nature of the latch connector parts  56  may cause the protrusions proximate the tips of the latch connector parts  56  to protrude into the lower groove connector part  134 , to engage at least one edge or shoulder of the cartridge  16  that at least partially defines or is proximate the lower groove connector part  134 , to form mechanical connections that arrest the relative movement when the apparatus  10  reaches the preactivated configuration. In the first embodiment, these mechanical connections are releasable snap-fit connections (e.g., the latch connector parts  56  may be referred to as flexible, resilient latches), although they may comprise other suitable connections. The mechanical connectors defined by the latch and lower groove connector parts  56 ,  134  may be referred to as at least one detent or at least one lower mechanical connector  56 ,  134 . Optionally, at least one of the retention ring  12  or the lower mechanical connector  56 ,  134  may be omitted. 
     In the first embodiment, at least the lower mechanical connector  56 ,  134  is a releasable connector that may be transitioned from a connecting state to an unconnecting state in response to predetermined relative movement between the receptacle  14  and the cartridge  16 . For example, such predetermined relative movement between the receptacle  14  and the cartridge  16  may be caused by a force being used in an effort to cause relative movement between the receptacle and cartridge exceeding a predetermined amount. Accordingly, if the retention ring  12  is omitted from the apparatus  10  or removed from the apparatus and it is desirable for the apparatus to be retained in the preactivated configuration, a method may include any force seeking to cause the relative movement between the receptacle  14  and the cartridge  16  not exceeding a predetermined amount that would be sufficient for causing the lower mechanical connector  56 ,  134  to become disconnected. 
     With the apparatus  10  in its preactivated configuration shown  FIG. 1 , the protective backing  20  may be removed and the adhesive membrane  22  may be engaged against a user&#39;s (e.g., patient&#39;s) skin to fasten the apparatus to the user&#39;s skin. The engagement will typically be facilitated through relative movement between the apparatus  10  and user. As the apparatus  10  is moved toward the user&#39;s skin, the microneedles of the microneedle assembly  24  may be the first features of the apparatus  10  to touch the user&#39;s skin since the microneedle assembly  24  is biased outwardly from the receptacle  14  due to the action of the force provider that may comprise the spring  46 . That is, the microneedle assembly  24  may engage the user&#39;s skin before the apparatus  10  is fastened to the user. In the first embodiment, when the apparatus  10  is initially engaged against the user&#39;s skin, the microneedle assembly  24  is engaged against the user&#39;s skin, and the engaging of the microneedle assembly against the user&#39;s skin causes or comprises compressing of the spring  46 . 
     The outwardly oriented, relatively releasable adhesive material of the adhesive membrane  22  fastens at least the receptacle&#39;s housing  30 ,  32  to the user, such that the adhesive membrane  22  may be referred to as a fastener. Alternatively, the fastening may be supplemented with, or replaced by, any other suitable fastening technique. For example, the apparatus  10 , or at least the receptacle&#39;s housing  30 ,  32 , may additionally or alternatively be fastened to the user using a fastening strap and/or any other suitable fastening features. 
     The apparatus  10  may conform at least somewhat to the contours of the user&#39;s body, and remain attached while allowing for at least some movement of the user&#39;s body, because of the relatively flexible nature of the outer body of the housing  30 , channel member  60  and adhesive membrane  22 , as well as the microneedle assembly  24  being movably mounted to the receptacle&#39;s housing  30 ,  32 , such as by way of the spring  46  and movably mounted sleeve  50 . The movability of the microneedle assembly  24  relative to the receptacle&#39;s housing  30 ,  32  may be controlled by the strength of the spring  46 , the flexibility of the adhesive membrane  22  spanning between the attachment flange  38  and the channel member  60 , and the selective engagement between the upper edge of the arresting flange  66  and the outer body  30 . 
     Depending upon a variety of factors, the flexibility of one or more of the outer body  30 , channel member  60  and adhesive membrane  22  may be adjusted or substantially eliminated. Similarly, the movability of the microneedle assembly  24  relative to the receptacle&#39;s housing  30 ,  32  may be adjusted or substantially eliminated, such by fixedly mounting the sleeve  50  to the receptacle&#39;s housing  30 ,  32  and eliminating the spring  46 . 
     Depending upon factors that may be associated with the stiffness of the spring  46 , flexibility of the adhesive membrane  22 , the size and number of the microneedles  74  and how far they protrude outwardly through the central opening in the adhesive membrane  22 , and/or the like, the microneedles may penetrate the user&#39;s skin in response to the apparatus  10  in its preactivated configuration being initially mounted to the user&#39;s skin by way of the adhesive membrane  22 . Alternatively or additionally, the microneedles may penetrate or at least further penetrate the user&#39;s skin in response subsequent pushing of the apparatus  10  against the user&#39;s skin, which may be facilitated by pushing the button disk  152 , such as, but not limited to, prior to removing the retention ring  12 , or the like, from the apparatus  10 . For example, the button disk  152  may be hit quickly with a hand or other suitable object to force the microneedles  74  into the user&#39;s skin. Once the microneedles  74  extend sufficiently into the user&#39;s skin, the relatively deformable or flexible nature of each of the outer body of the housing  30 , channel member  60  and adhesive membrane  22 , as well as the microneedle assembly  24  being movably mounted to the receptacle&#39;s housing  30 ,  32 , seek to allow the microneedles to sufficiently stay in the user&#39;s skin, even while the user moves his or her body to a reasonable extent. 
     At least partially reiterating from above and in accordance with one aspect of this disclosure, the spring  46  is a force provider or may be part of a force provider for forcing the microneedle assembly  24  outwardly relative to the housing  30 ,  32  of the receptacle  14  in a manner that seeks to allow the microneedles  74  to extend a sufficient distance outwardly from the receptacle subassembly  14  so that the microneedles sufficiently enter and stay in the user&#39;s skin. While the apparatus  10 , or at least the receptacle&#39;s housing  30 ,  32 , is fastened to the user as discussed above, the force provider that may comprise the spring  46  typically forces the microneedle assembly  24  outwardly relative to the receptacle&#39;s housing  30 ,  32  and against the skin of the user in a manner that seeks to ensure that there is sufficiently good contact between the microneedle assembly and the skin during delivery of the drug formulation. The force provider that may comprise the spring  46  seeks to ensure proper insertion of every microneedle of the microneedle array  24  into the skin, and it further seeks to ensure that the microneedles are maintained in the skin after insertion and until the apparatus  10  is removed following dosing. More generally, mechanical feature(s) comprising the spring  46 , the deformable membrane  22  and/or other suitable features seek to ensure proper insertion of the microneedles. The subject mechanical feature(s) may provide a substantially uniform force between the microneedles and skin through a spring and joint combination with rotational and translational degrees of freedom. The degrees of freedom and force seek to ensure that the microneedles and skin remain sufficiently engaged to one another during most body motions. The degrees of freedom also seek to prevent any damage to the microneedles. 
     With the apparatus  10  fastened to the user and the microneedle assembly  24  engaged against the skin of the user, the retention ring  12  or any other suitable retention device may be removed, or at least partially removed, from the remainder of the apparatus. The retention ring  12  may be removed by manually pulling the retention ring off of the controller  18 . Then, the button disk  152  may be pressed with a sufficient amount of force (e.g., a predetermined or more than a predetermined amount of force) for transitioning the lower mechanical connector  56 ,  134  from its connected state to its disconnected state. This transition to the disconnected state includes the protrusions proximate the tips of the latch connector parts  56  being forced out of the lower groove connector part  134 . Thereafter and in response to continued pressing of the button disk  152 , relative movement occurs between the receptacle  14  and cartridge  16 , which may again include the relative sliding between the protruding tips of the latch connector parts  56  and the outer housing or flange  122  of the cartridge  16 . In this regard,  FIG. 16  schematically illustrates the apparatus  10  in an intermediate configuration between the preactivated and activated configurations. 
     In response to further relative movement between the receptacle  14  and cartridge  16 , which may be caused by pushing the button disk  152 , the apparatus  10  reaches the activated configuration schematically shown in  FIG. 17 . As shown in  FIG. 17 , the cannula  92  has pierced the septum  108  so that the cavities  98 ,  100  of the cartridge  16  are in fluid communication with the plenum chamber  90  ( FIG. 6 ) of the receptacle  14 . That is, as shown in  FIG. 17 , the reservoir or cartridge  16  is in an inner position and in fluid communication with the microneedle assembly  24 . 
     In the preactivated configuration shown in  FIG. 15 , the reservoir or cartridge  16  is in an outer position and out of fluid communication with the microneedle assembly  24 . In the illustrated embodiment, the reservoir or cartridge  16  is for being pushed by the pushbutton or controller housing  26  so that the cartridge moves along a path from the outer position ( FIGS. 1 and 15 ) to the inner position ( FIG. 17 ). In the inner position, the reservoir or cartridge  16  is in fluid communication with the microneedle assembly  24 . The pushbutton or controller housing  26  may be pushed at least farther into the housing  30 ,  32  of the receptacle  14  for moving the reservoir or cartridge  16  along the path from the first position to the second position. The pushbutton or controller housing  26  may be more generally referred to as a pushing mechanism. In this regard, the pushbutton or controller housing  26  may be replaced with any other suitable pushing mechanism. 
     When the apparatus  10  reaches its activated configuration shown in  FIG. 17 , the relative movement between the receptacle  14  and cartridge  16  may be arrested in response engagement of at least one obstruction. The obstruction may comprise at least one releasable mechanical connection and/or at least one other engagement. For example, the lower cap  106  of the cartridge  16  may engage against an upper surface of the backing structure  72  of the receptacle  14  to restrict relative movement therebetween when the activated configuration is reached. Also, when the activated configuration is reached, the protruding tips of the latch connector parts  56  reach the upper groove connector part  132  ( FIGS. 8-10 ), so that the radially inwardly biased nature of the latch connector parts cause the protrusions proximate the tips of the latch connector parts  56  to protrude into the upper groove connector part  132 , to engage at least one edge or shoulder of the cartridge  16  that at least partially defines or is proximate the upper groove connector part  132 , to form mechanical connections that arrest the relative movement between the receptacle  14  and cartridge  16 . In the first embodiment, these mechanical connections are snap-fit connections and they may optionally be substantially unreleasable connections. The mechanical connectors defined by the latch and upper groove connector parts  56 ,  132  may be referred to as at least one detent or at least one upper mechanical connector  56 ,  132 . Optionally, the upper mechanical connector  56 ,  132  may be omitted. 
     In  FIG. 18 , some features, such as the button disk  152  of the controller housing  26  ( FIG. 14 ), have been removed to clarify the view. As shown in  FIG. 18 , the latch  144  is automatically opened in response to the pushbutton or controller housing  26  being pushed sufficiently far into the receptacle  14 , and the pushing mechanism or plunger  140  is released in response to the latch being opened. More specifically and as schematically shown by large arrows in  FIG. 18 , in response to the pushbutton or controller housing  26  being sufficiently pushed so that the apparatus  10  reaches or substantially approaches the activated configuration, the beveled surfaces  58 ,  170  ( FIGS. 4, 5, 11, 12, 14 and 17 ) of the sleeve  50  and latch  144  respectively engage one another. In response to sliding engagement between the beveled surfaces  58 ,  170 , the opposite actuating ends of the latch  144  are driven inwardly as schematically shown by large arrows in  FIG. 18 . As a result and as schematically shown by large arrows in  FIG. 19 , the latch  144  releases the plunger  140  and the spring  142  expands and, thus, forces the head  164  of the plunger against the deformable membrane  116  of the cartridge  16 . More specifically, in response to the opposite ends of the latch  144  being driven inwardly, the locking arms  174  bow outwardly and, thus, move out of the upper groove  166  in the shaft  162  of the plunger  140  so that the latch  144  releases the plunger  140  and the spring  142  drives the plunger. In the first embodiment, the latching mechanism or latch  144  is adapted to be transitioned between a latched state for restricting expansion of the spring  142 , and an unlatched state for allowing expansion of the spring  142 ; and the flexible membrane  22 , which is connected between the microneedle assembly  24  and the housing  30  of the receptacle subassembly  14  for both allowing and restricting expansion of the spring  142  independently of operation of the latch  144 . 
     As best understood with reference to  FIG. 20 , which illustrates a fully-activated or post-activated configuration of the apparatus  10 , the guide disk  146  and associated features may function as a guide apparatus that guides movement of the plunger  140  in a manner that seeks to ensure that substantially all of the drug formulation is forced out of the wide cavity  98  ( FIGS. 10 and 16 ). The guide disk  146  may be sufficiently deformable or flexible so that the inner edge of the guide disk remains within the lower groove  168  ( FIG. 13 ) in the shaft  162  of the plunger  140  while the plunger is moved by the spring  142  and the guide disk deforms. A central portion of the guide disk  146  deforms into a roughly conical shape (e.g., a substantially conical or substantially frustoconical shape) so that the plunger  140  is driven into the wide cavity  98  in a controlled manner. The guide disk  146  typically deforms such that the inner circular periphery of the guide disk remains both in the lower groove  168  and concentric with the outer circular periphery of the guide disk. This deformation and controlled movement of the guide disk  146  seeks to keep the plunger  140  axis substantially parallel and coincident with the axis of the wide cavity  98 . In this way the plunger  140  remains aligned with the wide cavity  98  and minimal, if any, fluid remains in the wide cavity  98  after the plunger has completed its motion. If there is any misalignment between the cartridge  16  and controller  18 , the guide disk  146  seeks to allow for compensating movement of the plunger  140  in a manner that seeks to keep the plunger  140  axis substantially parallel and coincident with the axis of the wide cavity  98 . The plunger  140  is movably mounted by way of the guide disk  146  in a manner that seeks to eliminate frictional forces that would inhibit movement of the plunger. 
     At least partially reiterating from above and in accordance with one aspect of this disclosure, the spring  142  is a force provider or may be part of a force provider for forcing the plunger  140  against the deformable membrane  116 . This force provider may include at least the spring  142 , one or more of the springs  142 , and/or any other suitable force providing features for flexing the deformable membrane  116 , or the like. Similarly, the plunger  140  may be more generally referred to as a pushing mechanism, and the plunger may be replaced by or supplemented with one or more other suitable pushing mechanisms. 
     The spring  142  drives the released plunger  140  against the reservoir or cartridge  16  for increasing the pressure of the fluid within the cartridge  16 , so that the fluid is supplied from the cartridge to the microneedle assembly  24 . More specifically, the spring  142  drives the released plunger  140  against the reservoir or cartridge  16  for at least partially collapsing the reservoir or cartridge, so that the fluid is supplied to the microneedle assembly  24 . More specifically and in accordance with the first embodiment, the spring  142  drives the plunger  140  so that its domed head  164  ( FIG. 14 ) causes the deformable membrane  116  to flex, and the domed head forces the deformable membrane  116  into contact with substantially the entire surface of the cartridge&#39;s body  96  that defines the wide cavity  98  ( FIGS. 10 and 16 ), so that substantially all of the drug formulation in the wide cavity  98  flows into the narrow cavity  100 . As indicated previously, the cartridge  16  comprises a container or reservoir, and the deformable membrane  116  being urged or forced into the wide cavity  98  may be characterized as the container or reservoir being at least partially collapsed. 
     The domed head  164  ( FIG. 14 ) may be configured so that the contact between the deformable membrane  116  and wide cavity  98  ( FIGS. 10 and 16 ) advances progressively from the widest area of the cavity  98  to the narrowest area of the cavity  98  so that substantially all of the drug formulation may be forced out of the cavity  98 . More specifically, the domed head  164  and the substantially bowl-shaped wide cavity  98  may be cooperatively configured, and the guide disk  146  may guide the plunger  140 , so that the contact between the deformable membrane  116  and wide cavity  98  advances progressively from the widest area of the cavity  98  to the narrowest area of the cavity  98 , so that substantially all of the drug formulation may be forced out of the cavity  98 . As another specific example, the curvature of the domed head  164  and the curvature of the bowl-shaped wide cavity  98  may be cooperatively selected in a manner that seeks to ensure that substantially all of the drug formulation is forced out of the cavity  98 . Reiterating from above, the respective end of the passageway extending between the cavities  98 ,  100  may be open proximate, or more specifically at, the central portion of the substantially concave or substantially bowl-shaped wall that at least partially defines the wide cavity  98 , and this configuration seeks to ensure that substantially all of the drug formulation is forced out of the cavity  98 . Alternatively, there may be some situations where it may not be desirable for all of the drug formulation to be forced out of the cavity  98 , or the like. 
     The drug formulation flows from the narrower cavity  100  through the cannula  92  into the plenum chamber  90  ( FIG. 6 ). In the first embodiment, the drug formulation exits the plenum chamber  90  by flowing through the rate control membrane and/or other suitable membrane on the top surface  78  of the support plate  76  and then through the apertures in the support plate to the channels associated with the microneedles  74 , and then into the user&#39;s skin. More generally, a force provider, which may comprise the spring  142 , at least indirectly forces the fluid to flow from the reservoir or cartridge  16  to the microneedle assembly  24  and then into the skin of the user, and the flowpath(s) between the reservoir or cartridge and the user&#39;s skin may be provided or defined in any suitable manner. 
     The drug formulation being forced out of the cavity  98  ( FIGS. 10 and 16 ) as discussed above may comprise the drug formulation being pressurized in a manner that causes the drug formulation to substantially uniformly fill the plenum chamber  90 , and flow through the rate control membrane and/or other suitable membrane on the top surface  78  of the support plate  76  to each of the microneedles  74 . The rate control membrane and/or other suitable membrane on the top surface  78  of the support plate  76  may be selected so that the pressure drop resulting from the drug formulation flowing through the rate control membrane and/or other suitable membrane substantially consumes all of the pressure energy imparted into the drug formulation through the action of the plunger  140 . As a result, there may be only capillary flow of the drug formulation through the microneedle assembly  24 . In addition or alternatively, forced flow of the drug formulation through the microneedle assembly  24  may be caused by the pressure energy imparted into the drug formulation through the action of the plunger  140 . 
     In one aspect of this disclosure, the delivery the drug formulation by the apparatus  10  may be by way of pressure driven flow and capillary flow. When the microneedles of the microneedle assembly  24  are is inserted into the skin and the apparatus  10  is in it actuated state, the microneedles may be wetted from interstitial fluid, and the drug solution may flow from the reservoir or cartridge  16  under pressure. The two liquid fronts may meet in or proximate the apertures defined in the support plate  76 , and then the drug formulation may flow freely into the skin. When the reservoir or cartridge  16  is emptied, capillary forces may draw at least some of, or substantially all of, the remaining drug formulation out of the apparatus  10  and into the skin. 
     In one aspect of this disclosure, the pushbutton or controller housing  26  may be referred to as an outer pushing mechanism, and the plunger  140  may be referred to as an inner pushing mechanism that is mounted to the outer pushing mechanism for being moved relative to the outer pushing mechanism for at least partially collapsing the reservoir or cartridge  16  in response to predetermined relative movement between the outer pushing mechanism and the housing  30 ,  32  of the receptacle  14 . At the occurrence of the predetermined relative movement between the housing  30 ,  32  and the outer pushing mechanism or controller housing  26 , the beveled surfaces  58 ,  170  ( FIGS. 4,5, 11, 12, 14 and 17 ) of the sleeve  50  and latch  144  respectively engage one another as discussed above, or the latch  144  may be opened in any other suitable manner. 
     In one example, the plunger  140  and deformable membrane  116  may be constructed of materials that are more deformable or flexible, and less rigid, than the material of the cartridge&#39;s body  96 , for helping to facilitate substantially all of the drug formulation being forced out of the wide cavity  98  ( FIGS. 10 and 16 ). For example and further regarding the movable member that may more specifically be in the form of the disk-shaped deformable membrane  116 , this deformable membrane may be formed from any suitably configured material that may be extensible, flexible, foldable, stretchable and/or the like. As a more specific example, the deformable membrane  116  may be a flexible non-porous film, such as polyisoprene film. In one example, the deformable membrane  116  may have very low fluid/vapor permeability and a low tensile modulus. For example, the water vapor transmission of the deformable membrane  116  would be low when used with water-based drug formulations. The tensile modulus of the deformable membrane  116  may be less than about 1.5 GPa, or more specifically less than 1.5 GPa. The low tensile modulus seeks to minimize the force required to fully deploy the plunger  140 . Alternatively, the deformable membrane  116  may have a higher tensile modulus, and a stronger spring  142  may be used. Suitable film laminates may be used as the deformable membrane  116 . 
     In the first embodiment of this disclosure, the deformable membrane  116  stretches to conform (e.g., substantially confirm) to the shape of the wide cavity  98  ( FIGS. 10 and 16 ). In addition or alternatively, the deformable membrane  116  may be configured for at least partially unfolding in a manner such that the deformable membrane substantially conforms to the shape of the wide cavity  98 . As a more specific example of an alternative embodiment, the deformable membrane  116  may be in the form of, substantially similar to, or at least partially in the form of a bellows, or the like, that unfolds to substantially conform to the shape of the wide cavity  98 . In this alternative embodiment, the deformable membrane  116  may not stretch, such that the deformable membrane  116  may be made from a non-extensible material. In another alternative embodiment, when a cavity at least partially defined by the deformable membrane  116  is filled the deformable membrane inflates outwardly relative to a flat base, and the head of the plunger  140  may be flat for flattening the inflated deformable membrane against the flat base. In another alternative embodiment, the cartridge  16  may be in the form of a deformable member such as a bag or bladder that is supported by a flat support surface, and the head of the plunger  140  may be flat for flattening the cartridge against the flat support surface. 
     More generally regarding materials from which the apparatus  10  may be constructed, suitable materials may be selected from those typically used for medical devices, such as medical devices for containing and dispensing drug formulations. As more specific examples, the springs  46 ,  142 , frame or bezel  70  and cannula  92  may be constructed of metal, such as stainless steel or any other suitable material. Other components of the apparatus  10  may be constructed from polymeric (e.g., plastic) materials. For example, the relatively flexible outer body  30  and channel member  60  of the receptacle  14  may be constructed of a natural rubber material. As a further example, the self-sealing septum  108  may comprise silicone and/or any other suitable materials. The body  96  of the reservoir or cartridge  16  may made of a rigid polymeric material such as, but not limited to, cyclic olefin polymer, and the cartridge may be sealed with polyisoprene or another suitable material. All of the various materials from which the apparatus  10  is constructed may be biocompatible and meet U.S. Pharmacopeial Convention requirements. 
     As mentioned above, the springs  46 ,  142  of the first embodiment may have different sizes and/or strengths as compared to one another. The spring  46  may be configured so that, while the apparatus  10  is fastened to a user as discussed above, the spring  46  forces the microneedle assembly  24  against the user&#39;s skin with a force in a range of 1 N to 10 N, or more generally in a range of about 1 N to about 10 N, or any other subranges therebetween. The force provided by the spring  142  may depend, for example, on the size of the microneedle assembly  24 , the rate control membrane and/or other suitable membrane that may be positioned at the top surface  78  of the microneedle assembly  24 , and the desired flow rate. The force provided by the spring  142  may be in a range of 1.1 N to 1.3 N, about 1.1 N to about 1.3 N, 2 N to 2.2 N, about 2 N to about 2.2 N, 2.4 N to 2.6 N, about 2.4 N to about 2.6 N, 2.7 N to 2.9 N, about 2.7 N to about 2.9 N or any other subranges therebetween. 
     More generally and reiterating from above, each of the springs  46 ,  142  may be more generally referred to as a force provider and/or may be replaced or supplemented with one or more suitable force providers. In such alternative embodiments, suitable force providers may include, but are not limited to, compressed foams, swellable polymers, pneumatic actuators, hydraulic actuators, electrical solenoid actuators, piezoelectric actuators, electrochemical actuators, rotary mechanical actuators and/or the like. 
     Referring to  FIGS. 21-23 , a second embodiment of this disclosure is like the first embodiment, except for variations noted and variations that will be apparent to those of ordinary skill in the art. For example, the second embodiment may be referred to as a second version or other modification of the first embodiment, or the like. Accordingly, the reference numerals used above are also used in the following discussion of the embodiment, or the like, illustrated in  FIGS. 21-23 . 
       FIGS. 21 and 22  are isolated pictorial views of the inner or lower support structure  52  (e.g., see  FIGS. 5 and 6 ), in accordance with the second embodiment, or the like. The lower support structure  52  may be in the form of a unity body having a base plate  200  with a centrally located, downwardly extending, tiered backing structure  72 . As shown in  FIG. 22 , the backing structure  72  may include a central partition  202  that is offset from the remainder of the base plate  200 . The lower surface of the partition  202  defines a side of the plenum chamber  90  ( FIGS. 6, 23 and 24 ), and the supply passageway  91  for at least partially receiving the cannula  92  ( FIGS. 5, 23 and 24 ) extends through the partition  202 . Referring to  FIG. 22 , each edge, or the like, of the partition  202  may be offset from the remainder of the base plate  200  by way of at least one step or shoulder  204  positioned between inner and outer risers  206 ,  208 . 
     As shown in  FIG. 22 , an annular peripheral flange  209  may extend downwardly from the periphery of the base plate  200 , so that the peripheral flange extends at least partially around each of the backing structure  72  and the annular inner and outer channels  84 ,  86  of the support structure  52 . The annular inner channel  84  may be at least partially defined between the shoulders  204  and inner risers  206 . The annular outer channel  86  may be at least partially defined between the outer risers  208  and the flange  209 . 
     As best understood with reference to  FIG. 21 , the lower support structure  52  may include one or more arresting lobes  66  that comprise truncated, chamfered or rounded corners of the base plate  200  and associated portions of the flange  209 . In addition, the lower support structure  52  may include an annular, upwardly facing lower seat  54  for the spring  46  ( FIGS. 5 and 23 ). Also, a cylindrical guide sleeve  212 , and a receptacle  214  for the sealing gasket  94  ( FIGS. 5 and 24 ), may extend upwardly from the central partition  202  of the backing structure  72 . 
     Referring also to  FIGS. 23 and 24 , the gasket  88  may be engaged in one or both of the inner and outer channels  84 ,  86 , so that the gasket  88  is engaged securely against the margin of the rate control membrane and/or other suitable membrane that forms or is positioned at the top surface  78  of the microneedle assembly  24 . These secure engagements associated with the gasket  88  may result at least partially from the frame  70  being fixedly mounted to the backing structure  72 , or more specifically frame  70  being fixedly mounted between the peripheral channel  82  of the microneedle assembly  24  and the outer channel  86  of the backing structure  72 . The frame  70  may be mounted between the peripheral and outer channels  82 ,  86  in any suitable manner. For example, at least one mounting member that may be in the form of an annular frame member  216  may be positioned in the outer channel  86  and fixedly mounted to the lower surface of the base plate  200 , such as by adhesive material, ultrasonic welding, mechanical fasteners and/or in any other suitable manner, wherein the outer marginal portion of the frame  70  is fixedly secured between the inner marginal portion of the frame member  216  and the lower surface of the base plate  200 . 
     As best understood with reference to  FIGS. 21 and 23 , the upper and lower support structures  50 ,  52  may be fixedly connected to one another by one or more snap-fit connections, wherein each snap-fit connection may comprise one or more flexible, resilient tabs or latches  218  ( FIG. 23 ) of the upper support structure that respectively extend through and are fixedly associated with holes or slots  210  of the lower support structure. More specifically, during relative movement between the upper and lower support structures  50 ,  52  that may be associated with assembly of the receptacle  14 , the free ends of the latches  218  of the upper support  50  may pass through the holes  210  of the lower support structure  52 , and the radially inwardly biased nature of the upper support&#39;s latch connector parts  218  may cause the protrusions proximate the tips of the upper support&#39;s latch connector parts  218  to engage at least one edge or shoulder of the lower support structure  52  that optionally at least partially defines or is proximate the holes  210  of the lower support structure  52 , to form mechanical connections that substantially fixedly connect the upper and lower support structures  50 ,  52  to one another. 
     Similarly and referring to  FIG. 23 , the cartridge and controller subassemblies  16 ,  18  may be fixedly connected to one another by one or more snap-fit connections, wherein each snap-fit connection may comprise one or more flexible, resilient tabs or latches  218  of the controller subassembly  18  that respectively extend through and are fixedly associated with holes or slots  210  in the wide closure  102  of the cartridge subassembly  16 . More specifically, during relative movement between the cartridge and controller subassemblies  16 ,  18  that may be associated with assembly of the apparatus  10 , the free ends of the latches  218  of the controller subassembly  18  may pass through the holes  210  of the cartridge subassembly  16 , and the radially inwardly biased nature of the controller subassembly&#39;s latch connector parts  218  may cause the protrusions proximate the tips of the controller subassembly&#39;s latch connector parts  218  to engage at least one edge or shoulder of the cartridge subassembly  16  that optionally at least partially defines or is proximate the holes  210  of the cartridge subassembly  16 , to form mechanical connections that substantially fixedly connect the cartridge and controller subassemblies  16 ,  18  to one another. At least partially reiterating from the foregoing, the controller subassembly  18  may include at least one flexible, resilient latch  218  extending outwardly relative to the controller subassembly&#39;s frame or housing  26  for connecting the controller subassembly to the cartridge subassembly  16 . 
     Throughout this disclosure, the positions of the latches  56 ,  218  and the edges or shoulders for respectively engaging the protrusions proximate the free ends of the latches may be interchanged with one another, and/or the snap-fit connections may be supplemented with or replaced by one or more other suitable connections. For example and at least partially reiterating from the foregoing, the controller subassembly  18  may include at least one flexible, resilient latch  218  extending outwardly relative to the controller subassembly&#39;s frame or housing  26  for connecting the controller subassembly to the cartridge subassembly  16  and/or the receptacle subassembly  14 ; and/or, even though not shown in the drawings, the cartridge subassembly  16  may include at least one flexible, resilient latch  218  extending outwardly relative to the cartridge subassembly&#39;s frame, housing, or the like, for connecting the cartridge subassembly to the controller subassembly and/or the receptacle subassembly  14 , or the like. 
     As at least partially shown in the drawings, the latches  56 ,  218  and the edges or shoulders for respectively engaging the protrusions proximate the free ends of the latches may be respectively arranged in substantially coaxially arranged in series that are spaced apart along the axis of the apparatus  10 . That is, the snap-fit connector parts (e.g., the latches  56 ,  218  and corresponding connector parts  132 ,  134 ,  210 ) may be respectively arranged in substantially coaxially arranged series that are spaced apart along the axis of the apparatus  10 . 
     Referring to  FIG. 23 , elongate channels  222  that extend outwardly from the narrow cavity  100  and are open to the wide cavity  98  ( FIGS. 10 and 16 ) may be included in the surface of the cartridge&#39;s body  96  that defines the wide cavity  98 . When the apparatus  10  is operated as discussed above so that the plunger  140  causes the deformable membrane  116  to flex into contact with substantially the entire surface of the cartridge&#39;s body  96  that defines the wide cavity  98 , the channels  222  may be operative in a manner that seeks to ensure that substantially all of the drug formulation in the wide cavity  98  flows into the narrow cavity  100 . 
     As best understood with reference to  FIGS. 21-23 , the lobes arresting lobes  66  may be arranged in a series that extends around the microneedle assembly  24 . Referring to  FIG. 23 , also when the apparatus  10  is being used as discussed above, the arresting lobes  66 , or the like, may temporarily engage the inner surface of the sidewall  34  of the outer body  30  in response to predetermined compression of the outer spring  46 . This engagement can be for restricting the microneedle assembly  24  from being pushed too far into the interior of the receptacle subassembly  14 . More specifically, this engagement can be for temporarily restricting further relative movement in one direction between the compound housing  30 ,  32  and the upper support structure  50  in a manner that seeks to prevent the microneedles  74  from becoming recessed into the receptacle  14  in a manner that may prevent the microneedles from being sufficiently inserted into a user&#39;s skin. That is, when (e.g., if) the outer spring  46  is sufficiently compressed during use, the arresting lobes  66  may temporarily engage the inner surface of the sidewall  34  of the outer body  30  for restricting further relative movement in one direction between the compound housing  30 ,  32  and the upper support structure  50  so that the microneedles  74  remain positioned sufficiently outwardly from the housing of the receptacle  14 , so that the microneedles remain sufficiently exposed for extending into a user&#39;s skin. 
     In accordance with one aspect of this disclosure, a least one arresting member may comprise the arresting flange or lobes  66 , wherein the a least one arresting member may be positioned between the microneedle assembly  24  and a housing of the apparatus, such as the housing  30 ,  32  of the receptacle  14 . The at least one arresting member, arresting flange or lobes  66  may be configured for restricting any movement of the microneedles  74 , or at least tips of the microneedles, into an interior of the housing of the receptacle. More specifically, the at least one arresting member, arresting flange or lobes  66  may be connected to and extend outwardly from the microneedle assembly  24  for engaging an interior surface of the housing  30 ,  32  of the receptacle  14  for restricting any movement of the microneedles  74 , or at least tips of the microneedles, into an interior of the housing of the receptacle. 
     Referring to  FIGS. 23 and 23 , also when the apparatus  10  is being used as discussed above, the lower or narrow closure  104 , or the like, of the cartridge subassembly  16  may move into the guide sleeve  212 , wherein sliding, guiding relative movement between the cartridge subassembly  16  and guide sleeve  212  seeks to ensure substantially coaxial insertion of the cannula  92  into the cartridge subassembly. 
     The above examples are in no way intended to limit the scope of the present invention. It will be understood by those skilled in the art that while the present disclosure has been discussed above with reference to exemplary embodiments, various additions, modifications and changes can be made thereto without departing from the spirit and scope of the inventions, some aspects of which are set forth in the following claims.