DESC:FIELD OF THE INVENTION

[0001] The present invention relates to intradermal delivery of drugs to a subject, and more particularly, to devices and systems for intradermal drug delivery and devices for use with drug delivery systems.
BACKGROUND

[0002] A drug or medicine may be delivered to a patient orally through the mouth or may be injected into the body through an injection. One of the common and easiest methods for drug delivery is through the skin. For example, an intravenous delivery of a drug is performed by injecting the drug directly into a blood vessel. Intraperitoneal delivery means when the drug is injected into the peritoneum. Subcutaneous delivery means delivery under the skin and intramuscular delivery is into a muscle.
[0003] Skin is the outermost protective layer of the body. It is composed of the epidermis, including the stratum corneum, the stratum granulosum, the stratum spinosum, the stratum basale, and the dermis, containing, among other things, the capillary layer. The stratum corneum is a tough, scaly layer made of dead cell tissue. It extends around 10–20 microns from the skin surface and has no blood supply. Intradermal injection (also intracutaneous or intradermic, abbreviated as ID) is a shallow or superficial injection of a substance (drug) into the dermis, which is located between the epidermis and the hypodermis of the skin.
[0004] Drug delivery through the skin has been relatively imprecise in both location and dosage of the pharmaceutical. Traditionally, shallow-depth injection is achieved by inserting a hypodermic needle relatively tangential to the skin surface, known as Mantoux method. Conventionally, in the Mantoux method, intradermal drug delivery is performed by a skilled medical professional using a hypodermic needle positioned bevel-up at a shallow angle relative to the skin surface. This requires skill on the part of the medical professional to insert the needle at a certain angle and depth. The skill requirement in this method makes the injection unreliable. Care is required to achieve the correct depth of penetration to ensure successful injection. In many cases, it has been reported that due to lack of skill and other extraneous factors, leakage or overly deep delivery may occur, which is not desirable and certainly avoidable.
[0005] An alternative is to insert the needle perpendicular to the skin surface. A needle approaching perpendicular to the skin may enhance reliability but gives rise to other issues. Since the penetration depth is low, a little shaking of the hands of the administrator can result in dislodging of the penetrated needle from under the skin.
[0006] Existing adapter designs for enabling tangential insertion of the needle into the skin have common issue that the needle is prone to rubbing onto the skin before puncturing the skin. This causes undesirable pain and discomfort to the patient. To accurately target shallow depths under the skin, an injection device with a needle projecting out of a depth-limiting surface, approaching perpendicular to the skin, is preferred.
[0007] Since the skin is a large, flexible organ, it tends to wrap around any approaching sharp object, such as a hollow hypodermic needle, before getting punctured. This puts a constraint on a minimum length of the needle that can reliably pierce through the skin while approaching the skin in a direction perpendicular to the skin and hence, achieve a minimum depth of drug delivery.
[0008] Even in cases where the puncturing of the skin is achieved with a shallow depth of needle penetration and injection pressure, the drug may leak out by creating a gap between the needle and the punctured skin. Therefore, to achieve shallow depth along with leakage-free drug delivery when the needle approaches perpendicular to the skin, it is critical that the skin gets punctured, and simultaneously forms a seal around the needle body.
[0009] There are existing techniques that attempt to achieve skin tensioning to improve the piercing ability of the skin during perpendicular insertion of a needle but none of such techniques are able to achieve enhanced skin gripping and sealing to ensure reliable and shallow depth delivery.
[0010] Shallow-depth injections have multiple benefits. First, they interact with a minimal number of nerve endings, making the injection procedures relatively less painful. Further, the skin houses many immune cells, which produce a superior immune response for many vaccines. Due to currently available nonreliable methods of shallow depth injections, these advantages cannot be fully tapped.
[0011] U.S. Patent Application No. 12/096,028 filed by Yeshurun, Yehoshua, et al. discloses a microneedle adapter suitable for pain injectors, with a pierceable septum for connection with the drug reservoir. However, the mechanism leaves dead volume between the pierceable septum and an adapter's inner bottom surface. Further, no mechanism is provided for skin sealing and gripping.
[0012] U.S. Patent No. 8,900,186 to Petis, et al, discloses a microneedle adapter with an injection pen. This device describes the skin interface of a post from where the needle protrudes for depth limiting, surrounded by space for accommodating intradermal bleb, surrounded by a ring. However, the mechanism leaves dead volume due to a backend needle length and provides no solution for skin gripping and sealing.
[0013] Additionally, drug delivery through the skin has been relatively imprecise in both location and dosage of the pharmaceutical. Some of the problems include movement of the patient during administration, delivery of incomplete dosages, and difficulties in delivering a pharmaceutical to the appropriate part of the skin. Even if the needle penetrates and stays under the skin, the fluid injection pressure can create gaps between the needle body and skin, creating a path for the drug to leak out. Therefore, it is desired and advantageous to be able to use small, precise volumes of pharmaceuticals for quick as well as long-term delivery through the skin.
[0014] Therefore, it is desirable to develop systems and methods that can eliminate one or more shortcomings associated with the abovementioned techniques.

SUMMARY

[0015] This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.
[0016] In one aspect, the disclosure provides an intradermal drug-delivery adapter for a drug delivery system. The intradermal drug-delivery adapter may be an adapter device or an adapter retrofittable to and for use with a drug delivery device such as drug delivery vehicle, e.g., a syringe or a drug delivery system to enable shallow depth injection of a drug to a subject receiving the drug.
[0017] The intradermal drug-delivery adapter comprises a skin-interface at a drug-delivery end of the adapter and a skin-pulling mechanism housed in a housing of the adapter. The skin-interface has an interface-profile configured to form an airtight enclosure when pressed against the skin of the subject receiving the drug. The skin-pulling mechanism is fluidly coupled to the airtight enclosure and is configured to generate sub-ambient pressure in the airtight enclosure. The interface-profile of the skin-interface comprises a plurality of concentric annular walls forming an inner enclosure and an outer enclosure of the airtight enclosure, wherein a skin-contacting edge of at least one of the plurality of annular walls has a curvature in a direction opposite to curvature of at least another of the plurality of annular walls. Further, the interface-profile of the skin-interface comprises at least one annular groove loop in a floor region of each of the inner enclosure and the outer enclosure and a groove track in the floor region fluidly connecting the inner enclosure and the outer enclosure via respective groove loops.
[0018] In an embodiment, a needle for injection may be fixed on the syringe. In another embodiment, a needle for injection is fixed on the adapter device. In another embodiment, the needle is detachable from the syringe and is removed from the syringe for attaching to the adapter device before use. In an embodiment, the needle is part of the adapter device and is already located and provided on the adapter device. In an alternate embodiment, the needle is a part of the drug delivery device / kit such as a syringe kit and is located on the syringe. In an embodiment, the adapter device includes the needle. The needle is a hypodermic needle for injection. The needle is attached to the adapter device. In an embodiment, the adapter device comes with and has the needle fixed on the delivery end of the adapter device. In an embodiment, the needle is removed from the syringe and fixed on the adapter device during and for operation of the adapter device.
[0019] In another aspect, the disclosure provides an adapter device fitted with a drug delivery vehicle such as a syringe to enable shallow-depth injection. In yet another aspect, the disclosure provides a system to enable shallow depth injection using the adapter device as in any of the aspects/embodiments above.
[0020] In an embodiment, the adapter device comprises means for attaching the adapter to the drug delivery (injecting) device of the drug delivery system. The means for attaching the adapter is configured for enabling the retrofitting of the adapter to a syringe such as a standard syringe with luer taper.
[0021] In an embodiment, the adapter device may have a substantially cylindrical shape, a cuboidal shape with beveled edges, or any other similar shape suitable for the application.
[0022] The adapter device has a syringe receiving end distal to the skin and a drug delivery end proximal to the skin. The adapter device houses the skin-pulling mechanism between the syringe receiving end and the drug delivery end. The skin-pulling mechanism is configured, during activation, for pulling the skin in a controlled manner to enable optimal and efficient delivery of the drug via the syringe. The skin-pulling mechanism comprises an air column connected to an air space formed between the skin and the contact surfaces of the drug delivery end when the device is held against the skin during operation. The skin-pulling mechanism, when activated, expands the air in the air column located inside the skin-pulling mechanism. The skin-pulling mechanism is configured to be in contact with the skin and during activation, the skin-pulling mechanism enables the pulling of the skin in a controlled manner to enable optimal and efficient delivery of the drug via the syringe.
[0023] In an embodiment, at the drug delivery end, the skin interface comprises a plurality of skin-contacting loops, a skin-contacting surface, groove loops, a groove track, and a vent hole. The air column is connected to the air space via the vent hole. The plurality of skin-contacting loops are concentric ring-shaped loops. In an embodiment, the skin-contacting surface and the groove loop are also concentric with the plurality of skin-contacting loops. A skin-contacting loop of the plurality of skin-contacting loops is the outermost of the concentric ring-shaped loops and forms an outermost peripheral loop of the skin interface, and has adhesive means for providing adhesion with the skin. At least one skin-contacting loop has an outward curve. At least one skin-contacting loop has an inward curve. The skin-contacting surface has a hole for the needle of the syringe to project out.
[0024] A set of the skin-contacting loops of the plurality of skin-contacting loops along with one of the groove loops form a cup-shaped geometry – an outer cup, on the drug delivery end of the adapter device. Similarly, another set of the skin-contacting loops, the skin-contacting surface, and one of the groove loops form another cup-shaped geometry – an inner cup, on the drug delivery end of the adapter device. It may be apparent that the inner cup is formed and located within the outer cup.
[0025] The vent hole forms a connection between the groove track and the skin-pulling mechanism. The skin-pulling mechanism, when activated, expands the air trapped in the airspace/enclosure formed between the skin and the skin interface to a larger space, thereby creating a vacuum effect in the enclosure. The larger space is created by activating the skin-pulling mechanism through the vent hole. This lowers the air pressure in the enclosure.
[0026] In an embodiment, during the use and operation of the adapter device, when the drug delivery end is in contact with the skin and the skin-pulling mechanism is activated, a portion of the skin near the needle is pulled laterally due to lower air pressure in the outer cup. Simultaneously, another portion of the skin near the needle is pulled towards the skin-contacting surface due to lower air pressure in the inner cup. This, in turn, ensures the formation of a perfect seal between the skin and the needle and an accurate penetration depth.
[0027] In an embodiment, the skin-pulling mechanism is a piston arrangement. The expansion of the air within the air column is achieved by a movement of a piston of the piston arrangement thereby reducing the pressure in the inner and the outer cup. In an embodiment, the piston is spring-loaded. In an embodiment, the piston is not spring-loaded.
[0028] In an embodiment, the adapter device comprises a trigger for controlling the movement of the piston. The trigger is operated upon by the medical practitioner by pulling it towards the syringe receiving end after ensuring that the skin interface is placed on and is in good contact with the skin of the receiver.
[0029] In an embodiment, during and for the operation of the adapter device, a length of the movement of the piston is fixed and predetermined from an initial position of the piston to a final position for creating a predetermined low pressure in the air space.
[0030] In some embodiments, to enable the movement of the piston during the operation of the adapter device, the trigger may be designed for different movements such as pushing, pulling, shifting, squeezing, and the like, resulting in the movement of the piston.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Figure 1A shows an isometric view of an adapter, in accordance with an embodiment of the invention;
Figure 1B and Figure 1C are partial section-views of the adapter corresponding to portions of Figure 1A, in accordance with an embodiment of the invention;
Figure 2 shows a sectional front view of a portion of the adapter device illustrating an interface profile of a skin-interface of the adapter, in accordance with an embodiment of the invention;
Figure 2A shows a detailed view of a portion of the front view in Figure 2;
Figure 3 is a front section-view of the adapter device in combination with a drug delivery system, in accordance with an embodiment of the invention;
Figures 4A-4C illustrate the adapter device in various views in accordance with an embodiment of the invention, wherein:
Figure 4A is a top view, Figure 4B is a sectional view at line A-A in Figure 4A, and Figure 4C is a detailed section view of a portion marked as ‘B’ in Figure 4B;
Figures 4D-4E show sectional views of portions of the adapter device in front view in accordance with an embodiment of the invention, wherein:
Figure 4D illustrates the interaction of the skin with an inner cup of the interface profile, and Figure 4E illustrates the interaction of the skin 190 with an outer cup of the interface profile;
Figure 5 illustrates the skin-pulling mechanism using a piston arrangement and the working/operation thereof, in accordance with an embodiment of the invention;
Figure 6 illustrates the skin-pulling mechanism, in accordance with another embodiment of the invention;
Figure 7 illustrates the skin-pulling mechanism, in accordance with yet another embodiment of the invention;
Figure 8 illustrates the skin-pulling mechanism, in accordance with yet another embodiment of the invention;
Figure 9 illustrates an exemplary stepwise operation and use of the adapter device when the adapter comes fixed with a needle, in accordance with an embodiment of the invention; and
Figure 10 illustrates another exemplary stepwise operation and use of the adapter device when the needle comes fixed on the syringe, in accordance with an embodiment of the invention.

[0032] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, a plurality of components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

[0033] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which invention belongs. The system and examples provided herein are illustrative only and not intended to be limiting.
[0034] For example, the term “some” as used herein may be understood as “none” or “one” or “more than one” or “all.” Therefore, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would fall under the definition of “some.” It should be appreciated by a person skilled in the art that the terminology and structure employed herein is for describing, teaching, and illuminating some embodiments and their specific features and elements and therefore, should not be construed to limit, restrict or reduce the spirit and scope of the present disclosure in any way.
[0035] For example, any terms used herein such as, “includes,” “comprises,” “has,” “consists,” and similar grammatical variants do not specify an exact limitation or restriction and certainly do not exclude the possible addition of a plurality of features or elements, unless otherwise stated. Further, such terms must not be taken to exclude the possible removal of the plurality of the listed features and elements, unless otherwise stated, for example, by using the limiting language including, but not limited to, “must comprise” or “needs to include.”
[0036] Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “plurality of features” or “plurality of elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “plurality of” or “at least one” feature or element does not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be a plurality of…” or “plurality of elements is required.”
[0037] Unless otherwise defined, all terms and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by a person ordinarily skilled in the art.
[0038] Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements of the present disclosure. Some embodiments have been described for the purpose of explaining the plurality of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.
[0039] Use of the phrases and/or terms including, but not limited to, “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or other variants thereof do not necessarily refer to the same embodiments. Unless otherwise specified, plurality of particular features and/or elements described in connection with plurality of embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although plurality of features and/or elements may be described herein in the context of only a single embodiment, or in the context of more than one embodiment, or in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.
[0040] Any particular and all details set forth herein are used in the context of some embodiments and therefore should not necessarily be taken as limiting factors to the proposed disclosure. Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[0041] In one aspect, the disclosure provides an adapter device retrofittable to and for use with a drug delivery device such as a syringe or a drug delivery system to enable shallow depth injection.
[0042] In an embodiment, a needle for injection is fixed on the syringe. In another embodiment, a needle for injection is fixed on the adapter device. In another embodiment, the needle is detachable from the syringe and is removed from the syringe for attaching to the adapter device before use. In another embodiment, the disclosure provides an adapter device fitted with a drug delivery device such as a syringe to enable shallow-depth injection. In yet another aspect, the disclosure provides a system to enable shallow depth injection using the adapter device as in any one of the aspects above.
[0043] In an embodiment, the adapter device comprises means for attaching the adapter to the drug delivery (injecting) device. The means for attaching the adapter is configured for enabling the retrofitting of the adapter to a syringe such as a standard syringe with luer taper.
[0044] Figure 1A shows an isometric view of an adapter 100A, in accordance with an embodiment of the invention. In an embodiment, the adapter 100A may have a substantially cylindrical shape, a cuboidal shape with bevelled edges, or any other similar shape. Herein, the adapter 100A (or the adapter device 100A) has a cylindrical shape. A receiver of the drug may be a subject such as a human or an animal. A receiver of the drug may be a patient, a subject under observation, a child receiving a vaccination, and the like. The receiver may be a human patient.
[0045] The adapter device 100A has a syringe receiving end 112 distal to a skin 190 of the subject and a drug delivery end 113 proximal to the skin 190. The adapter device 100A comprises a skin interface 100AIF for providing an interface with the skin 190 of the receiver, and a skin-pulling mechanism (not shown in Figure 1A) housed in a housing 100H of the adapter 100A. In an embodiment, the adapter device 100A comprises means for attaching the adapter device 100A to the drug delivery device such as the syringe of the drug delivery system.
[0046] The device 100A may be made of plastic generally used in medical applications such as Alkkaline Buta Strydin (ABS), Poly Propylene, Poly Carbonate, Acrylic, and like. Various features on the device 100A may be realized using high precision manufacturing techniques such as machining, microfabrication, molding, 3D Printing, etc.
[0047] The skin-interface 100AIF has an interface-profile configured to form an airtight enclosure when pressed against the skin 190. The skin-pulling mechanism is fluidly coupled to the airtight enclosure and is configured to generate sub-ambient pressure in the airtight enclosure. While administering the drug to the subject, the skin-pulling mechanism is configured, when activated, for pulling the skin, via the interface profile in a controlled manner to enable optimal and efficient delivery of the drug. The skin-pulling mechanism is connected to the enclosure via an air column.
[0048] Figure 1B and Figure 1C are partial section-views of the adapter 100A corresponding to portions 100A-B and 100A-C of Figure 1A and illustrate the structure of the interface-profile of the skin-interface 100AIF, in accordance with an embodiment of the invention. The interface-profile of the skin-interface 100AIF comprises a plurality of concentric annular walls (110, 120) forming an inner enclosure 120IE and an outer enclosure 110OE of the airtight enclosure. The airtight enclosure includes the inner enclosure 120IE and the outer enclosure 110OE and is connected to the air column. Further, the interface-profile of the skin-interface 100AIF comprises at least one annular groove loop (18O, 18I) in a floor region of each of the inner enclosure 120IE and the outer enclosure 110OE. Further, the interface-profile comprises a groove track 19 (shown in Figure 1A) in the floor region fluidly connecting the inner enclosure 120IE and the outer enclosure 110OE via respective groove loops 18I, 18O.
[0049] At least one skin-contacting edge (11,12,13, 15, 16) of at least one of the plurality of annular walls (110,120) has a curvature in a direction opposite to curvature of at least another skin-contacting edge (11,12,13, 15, 16) of the plurality of annular walls (110,120). A skin-contacting edge 16 of an annular wall 120 of the inner enclosure 120IE has a concave curvature towards the skin. A curvature radius of the inward curve of the skin-contacting loop 16 is between 0.1 mm to 5 mm.
[0050] A skin-contacting edge 12 of the annular wall 110 of the outer enclosure 110OE has a convex curvature towards the skin. In an embodiment, only a portion of the skin-contacting edge 16 of the annular wall 120 of the inner enclosure 120IE has a concave curvature towards the skin and the rest of a portion 15 of the skin-contacting edge 16 has a flat surface. An inner portion 13 of the skin-contacting edge of the annular wall 110 of the outer enclosure 110OE has a concave curvature towards the skin joined to the rest of a flat portion 11 of the skin-contacting edge via a portion 12 having a convex curvature towards the skin.
[0051] Figure 2 shows a sectional front view 100A-S of a portion of the adapter device 100A illustrating the interface profile of the skin-interface 100AIF, in accordance with an embodiment of the invention, wherein Figure 2A shows a detailed view of a portion A of the front view 100A-S illustrating the curve portions (concave/convex). Each of the at least one groove loop (18O, 18I) is recessed below a surrounding floor region of a floor region of the respective inner enclosure 120IE and the outer enclosure 110OE. The groove loop 18O is recessed below a surrounding floor region 18O-S of the outer enclosure 110OE. The groove loop 18I is recessed below a surrounding floor region 18I-S of the inner enclosure 120IE.
[0052] Further, in an embodiment, a depth DI of the floor region 18I-S of the inner enclosure 120IE is less than a depth DO of the floor region 18O-S of the outer enclosure 110OE.
[0053] In an embodiment, the adapter 100A may include means for attaching the adapter 100A to a drug delivery vehicle such as a syringe of the drug delivery system at the distal end 112. In an embodiment, the adapter 100A may include means for coupling the adapter 100A to the drug delivery vehicle of the drug delivery system and a receiving passage 100A-P disposed in a central longitudinal region of the housing 100H for providing passage to the drug delivery vehicle.
[0054] In an embodiment, the skin-contacting edge 11 of the annular wall 110 may have adhesive means for providing adhesion between the skin 190 and the adapter 100A. In an embodiment, only the flat portion of the skin-contacting edge 11 of the annular wall 110 may have adhesive means for providing adhesion between the skin 190 and the adapter 100A.
[0055] Figure 3 is a front section-view of the adapter device 100A in combination with the drug delivery system and illustrates the working of a skin-pulling mechanism 2, in accordance with an embodiment of the invention. The adapter device 100A houses the skin-pulling mechanism 2 between the syringe receiving end 112 and the drug delivery end 113. The skin-pulling mechanism 2 is located within the adapter device 100A between the drug delivery end 113 and the syringe receiving end 112. The skin-pulling mechanism 2 is configured, during activation, for pulling the skin 190 in a controlled manner to enable optimal and efficient delivery of the drug via the syringe.
[0056] The skin-pulling mechanism 2 comprises an air column 21. The air column 21 is connected to the airtight enclosure including the inner enclosure 120IE and the outer enclosure 110OE. The air column 21 is located towards the drug delivery end 113 with respect to a piston 22 of the skin-pulling mechanism 2. The skin-pulling mechanism 2, when activated, expands the air in the air column 21 located inside the skin-pulling mechanism 2. The skin-pulling mechanism 2 is configured to be in contact with the skin 190 and during activation, the skin-pulling mechanism 2, in conjunction with the interface profile, enables pulling of the skin 190 in a controlled manner to enable optimal and efficient delivery of the drug via the syringe.
[0057] Figure 3 also shows a needle 4 being used with the adapter device 100A. In an embodiment, the adapter 100A may include the needle 4 fixed at a central region of the skin interface 100AIF. The needle 4 is configured to deliver the drug via the drug delivery system. The adapter 100A may include means for coupling the needle 4 with the drug delivery vehicle (syringe) of the drug delivery system.
[0058] Referring again to Figures 1A-1C, in an embodiment when the adapter 100A is cylindrical in shape, the skin-contacting edges 11-16 are in the form of a skin-contacting loop 11, a skin-contacting loop 12, and so on. The adapter further includes a skin-contacting surface 17, groove loop 18I a groove track 19, and a vent hole 111. The air column 21 is connected to the airtight enclosure via the vent hole 111.
[0059] Figures 4A-4C illustrates the adapter device 100A in various views in accordance with an embodiment of the invention, wherein Figure 4A is a top view, Figure 4B is a sectional view at line A-A in Figure 4A, and Figure 4C is a detailed section view of a portion marked as ‘B’ in Figure 4B. The skin-contacting loops 11-16 are concentric ring-shaped loops. In an embodiment, the skin-contacting surface 17 and the groove loops 18O and 18I are also concentric with the skin-contacting loops 11-16. It may be apparent that any shape for any of the plurality of loops 11-16 may be chosen corresponding to the shape of the adapter 100A. Further, the shape of each of the skin-contacting loops 11-16 may differ from one another while remaining concentric to one another. The skin-contacting loop 11 of the plurality of skin-contacting loops 11-16 is the outermost of the concentric ring-shaped loops and forms an outermost peripheral loop of the skin-interface 100AIF.
[0060] In an embodiment, the skin-contacting loop 11 may include an adhesive means 11AM for providing adhesion with the skin 190. In an embodiment, the adhesive means 11AM may be a peelable adhesive tape, a suitable adhesive layer coated thereon, and the like. During the operation of the adapter device 100A, the adhesive means 11AM provided on the skin-contacting loop 11 closes any gap or undulations between the skin 190 preventing the escape of air.
[0061] In an embodiment, depending upon the size and shape of the adapter device 100A, the skin-contacting loop 11 may have a width in the order of and between the range of 0.5mm to 5mm.
[0062] The skin-contacting loop 12 is concentric to and within the skin-contacting loop 11. The skin-contacting loop 12 has an outward (convex) curve. A curvature radius of the outward curve of the skin-contacting loop 12 is between 0.1 mm to 5 mm. The outward curve of the skin-contacting loop 12 enables easy sliding of the skin 190 (along the surface formed by the skin-contacting loop 12 during activation of the skin-pulling mechanism 2.
[0063] The skin-contacting loop 13 is concentric to and located within the skin-contacting loop 12. The skin-contacting loop 13 has an inward (concave) curve. A curvature radius of the inward curve of the skin-contacting loop 13 is between 0.1 mm to 5 mm. During activation of the skin-pulling mechanism 2, the inward curve of the skin-contacting loop 13 enables capturing or locking of a portion of the skin 190 within the surface formed by the skin 190 contact loop 13.
[0064] The skin-contacting loop 14 is concentric to and located within the skin 190 contact loop 13. The groove loop 18O forms a depressed connection between the skin-contacting loop 13 and the skin-contacting loop 14. The skin-contacting loop 15 is concentric to and is located within skin-contacting loop 14. In an embodiment, the skin-contacting loops 14 and 15 are not curved and are flat as compared to the skin-contacting loops 12 and 13.
[0065] The skin-contacting loop 16 is concentric to and located within the skin-contacting loop 15. The skin-contacting loop 16 has an inward (concave) curve. A curvature radius of the inward curve of the skin-contacting loop 16 is between 0.1 mm to 5 mm.
[0066] The skin-contacting surface 17 is located within the skin-contacting loop 16. The skin-contacting surface 17 is flat. The groove loop 18I forms a depressed connection between the skin-contacting loop 16 and the skin-contacting surface 17.
[0067] The skin-contacting surface 17 has a hole for the needle 4. In an embodiment, during an operation of the device 100A, the needle 4 projects out of the hole of the skin-contacting surface 17 for penetrating the skin 190 of the receiver. In an embodiment, the needle 4 is part of the adapter device 100A and is already located and provided on the adapter device 100A. In an alternate embodiment, the needle 4 is a part of the drug delivery device / kit such as a syringe kit and is located on the syringe.
[0068] The skin-contacting loops 11-16 are concentric ring-shaped loops. In an embodiment, the skin-contacting surface 17 and the groove loops 18O, 18I are also concentric with the skin-contacting loops 11-16. It may be apparent that any shape for any of the plurality of loops 11-16 may be chosen corresponding to the shape of the adapter device 100A. Further, the shape of each of the skin-contacting loops 11-16 may differ from one another while remaining concentric to one another.
[0069] Referring again to Figures 1B and 1C, in an embodiment, the skin-contacting loops 11, 12, 13, and 14 along with the groove loop 18O form a cup-shaped geometry: an outer cup corresponding to the outer enclosure 110OE of the adapter device 100A. Similarly, the skin-contacting loops 15 and 16, the skin-contacting surface 17, and the groove loop 18I form another cup-shaped geometry: an inner cup corresponding to the inner enclosure 120IE of the adapter device 100A. It may be apparent that the inner cup is formed and located within the outer cup. The outer cup projects out of the skin-contacting loop 14 by a distance of about DO-DI or about 0.5 to 5 mm, which defines the depth of the outer cup and is connected by a pillar structure.
[0070] The groove track 19 connects the groove loop 18O and the groove loop 18I. The vent hole 111 on the groove track 19 forms a connection between the groove track 19 and the skin-pulling mechanism 2. In an embodiment, the vent hole 111 may be provided on one of the groove loops 18O, 18I.
[0071] Figures 4D-4E show sectional views of portions of the adapter device 100A in front view in accordance with an embodiment of the invention, wherein Figure 4D illustrates the interaction of the skin 190 with the inner cup of the interface profile forming the inner enclosure 120IE and Figure 4E illustrates the interaction of the skin 190 with the outer cup of the interface profile forming the outer enclosure 110OE. During operation, when the device 100A is pressed against the skin 190, the skin-pulling mechanism 2, when activated, expands the air trapped in the air space/ airtight enclosure formed between the skin 190 and the skin-interface 100AIF to a larger space, thereby creating a vacuum effect or sub ambient pressure in the enclosure. The larger space is created by activating the skin-pulling mechanism 2 through the vent hole 111. This lowers the air pressure in the enclosures.
[0072] The groove track 19 may have a depth and a width in the order of and between 0.1 to 2 mm. The depth and the width of the groove track 19 are chosen such that the skin 190 when flexed during the activation and working of the device 100 cannot reach to make contact with a bottom surface of the groove loops 18O, 18I. This ensures that the skin 190 is unable to and cannot block the vent hole 111, thereby ensuring the expansion of air trapped in the enclosure into the space created by the activation of the skin-pulling mechanism 2. The groove track 19 acts as a path for transmitting the low air pressure created by the activation of the skin-pulling mechanism 2 to the groove loop 18O. The groove loop 18O ensures uniform distribution of the low pressure throughout the outer cup.
[0073] Similarly, the groove loops (18O, 18I) have a depth and a width in the order of and between 0.1 to 2 mm such that the skin 190 cannot make contact with the bottom surface of the groove loop (18O, 18I) even when flexed during operation. The groove loop 18I has a depth and a width in the order of and between 0.1 mm to 2 mm such that the skin 190 cannot reach to touch a bottom surface of the groove loop 18I when flexed. The groove track 19 transmits the low air pressure created by the skin-pulling mechanism 2 to the groove loop 18I, which results in an active pulling of the skin 190 towards the needle 4.
[0074] The depth DO of the outer cup is defined by the perpendicular distance between the skin-contacting loop 11 and the skin-contacting loop 14 and provides space for the skin 190 to enter and get entrapped into, for firm placement of the adapter device 100A against the skin 190 upon activation of the skin-pulling mechanism 2. Due to the firm placement so achieved, the outer cup also prevents dislodging of the needle 4 due to minor shaking of hands of the administrator. The depth DO of the outer cup is in the order of between 0.5 mm to 5 mm. The needle 4 projecting out of the skin-contacting surface 17 lies within the inner cup.
[0075] In an embodiment, during use and operation of device 100A, when the drug delivery end 113 is in contact with the skin 190 and the skin-pulling mechanism 2 is activated, a portion of the skin 190 near the needle 4 is pulled laterally due to lower air pressure in the outer cup. Simultaneously, another portion of the skin 190 near the needle 4 is pulled towards the skin-contacting surface 17 due to lower air pressure in the inner cup.
[0076] The groove loop 18I and the groove track 19 enable air drainage between the skin 190 and the skin-contacting surface 17 ensuring perfect resting of the skin 190 against the skin-contacting surface 17. This, in turn, ensures the formation of a perfect seal between the skin 190 and the needle 4 and an accurate penetration depth.
[0077] The skin-pulling mechanism 2, upon activation, expands the air column 21 located inside the skin-pulling mechanism 2. The air column 21 is connected to the air space formed between the skin 190 and the skin-contacting surfaces on the drug delivery end 113. As a result of which, the airspace expands, thereby lowering the air pressure in the inner cup and the outer cup.
[0078] In an embodiment, the skin-pulling mechanism 2 is a piston arrangement. The expansion of the air within the air column 21 is achieved by a movement of a piston 22 of the piston arrangement thereby reducing the pressure in the inner and the outer cup. As an example, the amount of the reduction of pressure may be in the order of and between 20 mbar to 800 mbar [0.02-0.8 bar] below atmospheric pressure.
[0079] In an embodiment, the adapter device 100A comprises a trigger 23 for controlling the movement of the piston 22. The trigger 23 is operated upon by the medical practitioner by pulling it towards the syringe receiving end 112 after ensuring that the skin-interface 100AIF is placed on and is in good contact with the skin 190 of the receiver. In an embodiment, during and for the operation of adapter device 100A, a length of the movement of the piston 22 is fixed and predetermined from an initial position of the piston 22 to a final position for creating a low pressure in the air space. In an embodiment, the piston 22 is spring-loaded. In an embodiment, the piston 22 is not spring-loaded.
[0080] Figure 5 illustrates the skin-pulling mechanism 2 using a piston arrangement 500 and the working/operation thereof, in accordance with an embodiment of the invention. The skin-pulling mechanism 2 comprises the piston arrangement 500 and a trigger 23 in the form of lugs protruding out from the housing 100H of the adapter 100A. The piston arrangement 500 includes a piston 22 and is configured to generate the sub-ambient pressure in the airtight enclosure. The trigger 23 is configured to move the piston 22 of the piston arrangement 500 upon being activating by a user of the drug delivery system. The user may be a drug delivery administrator or a medical practitioner.
[0081] Fingers of the administrator/medical practitioner may be placed on the trigger 23 of the skin-pulling mechanism 2 as shown in Figure 5B. Figure 5C shows the piston 22 of the piston arrangement 500 in an initial position. Figure 5D shows the piston 22 in a final position after being pulled back by the medical practitioner, as a result of which, a low-pressure is created in the air space / the airtight enclosure.
[0082] Figure 6 illustrates the skin-pulling mechanism 2 using a piston arrangement 600 and the working/operation thereof, in accordance with another embodiment of the invention. The fingers of the administrator/medical practitioner may be placed on the trigger 23 as shown in Figure 6B. Figure 6C shows the piston 22 in an initial position. When the trigger 23 is pushed, the piston 22 moves up from the initial position. Figure 6D shows the piston 22 in a final position after being pushed by the medical practitioner, as a result of which, a low pressure is created in the air space / the airtight enclosure. In this embodiment, low air pressure is created behind the piston 22 as compared to the embodiment of Figure 5. Figure 6C and Figure 6D also show the air path movement as the piston 22 moves and creates the low pressure in the air space.
[0083] Figure 7 illustrates the skin-pulling mechanism 2 using a piston arrangement 700 and the working/operation thereof, in accordance with yet another embodiment of the invention. Herein, the skin-pulling mechanism 2 comprises the piston arrangement 700 and a trigger 23 in the form of a lug protruding out from a slot 710 in the housing 100H of the adapter 100A. The piston arrangement includes a piston 22 and a spring. The piston 22 is configured to generate the sub-ambient pressure in the airtight enclosure and is loaded with the spring. The trigger 23 is configured to toggle, upon being activating by the user, between an initial position and a final position within the slot 710 to move the piston 22. In this embodiment, the piston 22 is spring loaded and for operating the adapter device 100A, the trigger 23 is toggled between the initial position and the final position of the trigger 23 as shown in Figure 7B.
[0084] In some embodiments, for enabling the movement of the piston 22 during the operation of the adapter device 100A, the trigger 23 may be designed for different movements such as pushing, pulling, shifting, squeezing, and the like, resulting in the movement of piston 22. It may be apparent that the trigger 23 and the piston arrangement may be designed based on design requirements such as form factor, material strength, weight, practitioner preferences, and the like.
[0085] The medical practitioner may toggle the trigger 23 between the initial position and the final position of the trigger 23 for the operation of the adapter device 100A along the path shown in Figure 7B. Figure 7C shows the piston 22 in an initial position where the piston 22 is held in a locked position using the trigger 23. When the trigger 23 is toggled, the piston 22 moves back from its initial position due to the spring force. Figure 7D shows the piston 22 in a final position after being moved back due to the spring force, as a result of which, a low-pressure is created in the air space.
[0086] Figure 8 illustrates the skin-pulling mechanism 2 using a piston arrangement 800 and the working/operation thereof, in accordance with yet another embodiment of the invention. The skin-pulling mechanism 2 comprises the piston arrangement 800 and a trigger 23. The piston arrangement 800 comprises a spring and a piston 22 configured to generate the sub-ambient pressure in the airtight enclosure. The piston is loaded with the spring. The trigger 23 is integral with the piston and protrudes out from a slot 810 in the housing 100H of the adapter 100A. The trigger is configured to move, upon being activating by a user, between an initial position and a final position within the slot 810 to move the piston 22.
[0087] In this embodiment, the piston 22 is spring loaded and for operating the adapter device 100A, the trigger 23 is an integral part of the piston 22. The trigger 23 is located on the piston 22 and is an integral part of the piston 22. The trigger 23 is a button 23 on the piston 22. That is to say, in this embodiment, the practitioner is directly applying force on the piston 22 against the spring when moving the toggle 23 (and so the piston 22) between an initial position and a final position as shown in Figures 8C and 8D. The medical practitioner presses the button 23 between the initial position and the final position for operation of the adapter device 100A along the path shown in Figures 8D and 8E. Figure 8C shows the piston 22 in an initial position. When the button 23 is pressed, the piston 22 moves inwards towards a centre of the adapter device 100A. For operation and use of the device 100A, the button 23 is pressed by the medical practitioner before the device 100A is placed on the skin 190 to make a good contact with the skin 190. Figure 8D shows the piston 22 in an intermediate position, wherein the button 23 is pressed and the adapter device 100A is in a squeezed position. Figure 8E shows the final position of the piston 22 when the button 23 has been released and the piston 22 has moved outward from the intermediate position to a final position due to the spring force, as a result of which, a low pressure is created in the air space.
[0088] Figure 9 illustrates an exemplary stepwise operation and use of the adapter device 100A when the adapter comes fixed with the needle 4. Here, the needle 4 is fixed and attached to the adapter device 100A. In this embodiment, the syringe 3 may come prefilled with the drug. In this embodiment, the syringe 3 may be filled by other means. As an example, in this embodiment, the syringe 3 may come with a needle which may be removed and disposed of after filling the drug. As an example, in this embodiment, the syringe 3 may come with a drug-filling needle hub 904 having a drug-filling needle 904dfn which may be removed and disposed after filling the syringe 3. Here, at least one of the drug-filling needle hubs 904 and the drug-filling needle 904dfn is detached from the syringe 3 after the drug is filled in the body of the syringe 3. Subsequently, the syringe 3 is ready for attaching to the adapter device 100A for use and operation.
[0089] As shown in Figure 9A, at step 1, a body of the syringe 3 is filled with the drug from a vial by sucking operation of the syringe 3. As shown in Figure 9B, at step 2, the needle hub 904 is removed from the syringe 3, leaving behind the drug in the body of the syringe 3. As shown in Figure 9C, at step 3, the adapter device 100A is attached to the syringe 3. As shown in Figure 9D, at step 4, the adapter device 100A is attached to the body of the syringe 3 and the assembly so formed is ready for use on the receiver.
[0090] Figure 10 illustrates another exemplary stepwise operation and use of the adapter device 100A when the needle 4 comes fixed on the syringe 3, in accordance with an embodiment of the invention. The needle 4 is attached to a body of syringe 3. The syringe 3 includes a needle hub 1004 holding the needle 4. As shown in Figure 10A, at step 1, a body of the syringe 3 is filled with the drug from a vial by a sucking operation of the syringe 3. As shown in Figure 10B, at step 2, the adapter device 100A (without the needle 4) is attached to the syringe 3. As shown in Figure 10C, at step 3, the adapter device 100A is attached to the body of the syringe 3 and the assembly so formed is ready for use on the receiver.
[0091] The invention of the disclosure ensures reliable shallow-depth penetration and leakage-free fluid entry into the body. The invention enables enhanced gripping of the skin 190 during drug delivery to foolproof the injection of the drug with regards to human errors such as patient movement, shaky hands of the administrator, and the like. Further, due to the pressure control achieved by the use of the spring and fixed movement of the trigger 23, the invention is able to provide fool-proof perfect seal formation between needle 4 and skin 190 to avoid leakage and improve the reliability of the injection.
[0092] The adapter device 100A of the invention retrofits to standard syringes. The adapter device 100A is disposable and easy to manufacture. The design of the adapter device 100A of the invention enables mass production as the shape is suited for injection molding and other cheaper mass production methods.
[0093] The invention enables mechanisms for skin 190 gripping and sealing in a completely disposable format, enabling the device's utilization in masses. Also, since the features of the invention involve the use of scalable manufacturing processes such as plastic injection moulding, grinding, machining, and simple assembly processes, the production of the device in bulk can be achieved at competitive costs. The availability of a reliable shallow-depth injection device such as that of the invention will also promote the development of new drugs designed for shallow-depth actions.
[0094] The invention enables enhanced gripping of the skin during drug delivery to foolproof the injection of the drug with regard to human errors such as patient movement, shaky hands of the administrator, and the like. Further, the invention provides perfect seal formation between needle and skin to avoid leakage and improve the reliability of the injection.
[0095] The invention also provides systems and devices that can work with standard available methods and devices such as standard syringes by retrofitting to existing methods and systems and providing the advantage of foolproofing human errors and sealing as mentioned above.
[0096] The adapter of the invention is cheap to manufacture as mass-production article and can be applied as disposable one-time-use devices. This is preferred in medical applications to reduce repetitive sterilization costs and fool-proofing against contamination. Further, the invention also provides for reduction in dentations on the skin and leave minimal or no markings on the skin. The tension provided is controlled and optimum, and smooth to minimize discomfort to the patient/subject.
[0097] While specific language has been used to describe the present subject matter, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. ,CLAIMS:1. An intradermal drug-delivery adapter (100A) for a drug delivery system, the adapter (100A) comprising:
a skin-interface (100-AIF) at a drug-delivery end of the adapter (100A), the skin-interface (100-AIF) having an interface-profile configured to form an airtight enclosure when pressed against the skin (190) of a subject receiving the drug; and
a skin-pulling mechanism (2) housed in a housing (100H) of the adapter (100A), the skin-pulling mechanism (2) being fluidly coupled to the airtight enclosure and being configured to generate sub-ambient pressure in the airtight enclosure;
wherein the interface-profile of the skin-interface (100-AIF) comprises:
a plurality of concentric annular walls (110, 120) forming an inner enclosure (120IE) and an outer enclosure (110OE) of the airtight enclosure, wherein a skin-contacting edge of at least one of the plurality of annular walls (110, 120) has a curvature in a direction opposite to curvature of at least another skin-contacting edge of the plurality of annular walls (110, 120);
at least one annular groove loop (18I, 18O) in a floor region of each of the inner enclosure (120IE) and the outer enclosure (110OE); and
a groove track (19) in the floor region fluidly connecting the inner enclosure (120IE) and the outer enclosure (110OE) via respective groove loops (18I, 18O).
2. The adapter (100A) as claimed in claim 1, wherein each of the at least one groove loop (18I, 18O) is recessed below a surrounding floor region of respective inner enclosure (120IE) and outer enclosure (110OE).
3. The adapter (100A) as claimed in claim 1, wherein a depth (DI) of a floor region of the inner enclosure (120IE) is less than a depth (DO) of a floor region of the outer enclosure (110OE).
4. The adapter (100A) as claimed in claim 1, wherein:
a skin-contacting edge of an annular wall of the inner enclosure (120IE) has a concave curvature towards the skin; and
a skin-contacting edge of an annular wall of the outer enclosure (110OE) has a convex curvature towards the skin.
5. The adapter (100A) as claimed in claim 1, wherein:
a portion of a skin-contacting edge of an annular wall of the inner enclosure (120IE) has a concave curvature towards the skin (190) and the rest of the skin-contacting edge has a flat surface; and
an inner portion of a skin-contacting edge of the annular wall of the outer enclosure (110OE) has a concave curvature towards the skin (190) joined to the rest of a flat portion of the skin-contacting edge via a portion having a convex curvature towards the skin.
6. The adapter (100A) as claimed in claim 1 further comprises, at a distal end of the adapter (100A), means for attaching the adapter (100A) to a drug delivery vehicle of the drug delivery system.
7. The adapter (100A) as claimed in claim 1, wherein a skin-contacting edge of the annular wall of the outer enclosure (110OE) has adhesive means for providing adhesion between the skin (190) and the adapter (100A).
8. The adapter (100A) as claimed in claim 1 comprises:
means for coupling the adapter (100A) to a drug delivery vehicle of the drug delivery system; and
a receiving passage disposed in a central longitudinal region of the housing (100H) for providing passage to the drug delivery vehicle.
9. The adapter (100A) as claimed in claim 1 comprises:
a needle (4) fixed at a central region of the skin (190) interface, the needle (4) being configured to deliver the drug via the drug delivery system; and
means for coupling the needle (4) with a drug delivery vehicle of the drug delivery system.
10. The adapter (100A) as claimed in claim 1, wherein the skin-pulling mechanism (2) comprises:
a piston arrangement (500, 600, 700, 800), the piston arrangement (500, 600, 700, 800) comprises a piston (22) configured to generate the sub-ambient pressure in the airtight enclosure; and
a trigger (23) in the form of lugs protruding out from the housing (100H) of the adapter (100A), the trigger (23) being configured to move the piston (22) of the piston arrangement (500, 600, 700, 800) upon being activating by a user of the drug delivery system.
11. The adapter (100A) as claimed in claim 1, wherein the skin-pulling mechanism (2) comprises:
a piston arrangement (500, 600, 700, 800), the piston arrangement (500, 600, 700, 800) comprises a spring and a piston (22) configured to generate the sub-ambient pressure in the airtight enclosure, the piston (22) being loaded with the spring; and
a trigger (23) in the form of a lug protruding out from a slot in the housing (100H) of the adapter (100A), the trigger (23) being configured to toggle, upon being activating by a user, between an initial position and a final position within the slot to move the piston (22).
12. The adapter (100A) as claimed in claim 1, wherein the skin-pulling mechanism (2) comprises:
a piston arrangement (500, 600, 700, 800), the piston arrangement (500, 600, 700, 800) comprises a spring and a piston (22) configured to generate the sub-ambient pressure in the airtight enclosure, the piston (22) being loaded with the spring; and
a trigger (23), integral with the piston, protruding out from a slot in the housing (100H) of the adapter (100A), the trigger (23) being configured to move, upon being activating by a user, between an initial position and a final position within the slot to move the piston (22).