introduced into the cavity of the housing, the substance producing the dispensing enhancing pressure in the cavity.
These and other objects of the invention are substantially achieved by providing an intradermal delivery device comprising a housing having an internal cavity dimensioned to 5 receive a substance for delivery to a patient, a skin penetrating device in fluid communication with the cavity, and a resiliently biased movable member in fluid communication with the cavity. The resiliently biased movable member produces a dispensing enhancing pressure in the cavity for 1° dispensing the substance from the cavity to the skin penetrating member and indicates the delivery of a sufficient amount of the substance to the patient.
The objects and advantages of the invention are further attained by providing an intradermal delivery device com- 15 prising a housing having at least a portion made of an expandable material with sufficient elasticity to produce a dispensing enhancing pressure when the cavity is filled with a substance and to indicate that the cavity has not yet delivered a sufficient amount of the substance. A skin 20 penetrating device is coupled to the housing and is in fluid communication with the cavity.
The present invention is directed to a device for delivering a substance into the skin of a patient. More particularly, the invention is directed to an intradermal delivery device and to 25 a method for administering a substance below the stratum corneum of the skin of a patient where the substance is absorbed and utilized by the body.
As used herein, the term "penetrate" refers to entering an 3Q object, such as a layer of the skin, without passing completely through. The term "pierce" refers to passing completely through an object, such as a layer of the skin.
The device and method of the present invention are suitable for use in administering various substances, includ- 35 ing pharmaceutical agents, to a patient, and particularly to a human patient. As the term is used herein, a pharmaceutical agent includes a substance having biological activity that can be delivered through the body membranes and surfaces, particularly the skin. Examples of pharmaceutical agents 40 include antibiotics, antiviral agents, analgesics, anesthetics, anorexics, antiarthritics, antidepressants, antihistamines, anti-inflammatory agents, antineoplastic agents, vaccines, including DNA vaccines, and the like. Other substances that can be delivered intradermally to a patient include proteins, 45 peptides and fragments thereof. The proteins and peptides can be naturally occurring, synthesized or recombinantly produced.
The delivery device of the present invention is constructed for penetrating selected layers of the dermis of a 50 patient to attain the desired depth of penetration. The desired depth of penetration is determined by the substance being delivered and the desired rate of absorption by the body. Less penetration speeds the uptake of the substance by the body, and greater penetration slows delivery. It is contem- 55 plated that the skin penetrating member has a length of about 50 microns to about 1,500 microns. It is also contemplated that an array of such skin penetrating members can be used. The penetrating members have a length designed to pierce the stratum corneum without inducing pain by impacting 60 nerve endings. By delivering a substance below the stratum corneum, the substance can be absorbed and utilized by the body substantially without pain or discomfort to the patient. Preferably, the skin penetrating members have a length and diameter to penetrate the skin to a depth where the patient 65 experiences little or no pain, for example, below the stratum corneum and above the nerve endings.
The present invention is directed to an intradermal delivery device for delivering a substance into the skin of a patient where the device is able to maintain a dispensing enhancing pressure for delivering the substance. More particularly, the invention is directed to a unit dose delivery device for the sustained delivery of a substance through the skin of a patient.
The objects, advantages and other salient features of the invention will become apparent from the following detailed description which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The following is a brief description of the drawings:
FIG. 1 is a top view of a delivery device in accordance with a first embodiment of the invention;
FIG. 2 is a front elevational view of the device of FIG. 1;
FIG. 3 is a bottom view of the device of FIG. 1, showing a skin penetrating device;
FIG. 4 is an enlarged partial cross-sectional view of the device of FIG. 2, showing the skin penetrating device 3 bonded to a housing;
FIG. 5 is an enlarged cross-sectional view taken along the line 5—5 in FIG. 1, showing a cavity in the housing and a diaphragm in a normal, relaxed state;
FIG. 6 is a cross-sectional view similar to FIG. 5 but showing the cavity filled with a substance and the diaphragm in a stretched state for producing an indication of an insufficient amount dispensed and a dispensing enhancing pressure;
FIG. 7Ais a cross-sectional side view of a delivery device in accordance with a second embodiment of the invention, wherein the device has an expandable diaphragm forming a top wall;
FIG. 7B is a top view of the device of FIG. 7A;
FIG. 8 is a cross-sectional side view similar to FIG. 7A but with the cavity filled with a substance and the diaphragm in the stretched state;
FIG. 9 is a top view of a delivery device in accordance with a third embodiment of the invention showing an inlet port and an expandable diaphragm in a top wall;
FIG. 10 is a bottom view of the delivery device of FIG.
FIG. 11 is an enlarged cross-sectional view taken alone the line 11—11 in FIG. 9;
FIG. 12 is a top view of a delivery device in accordance with a fourth embodiment of the invention, showing an expandable top wall and an inlet port coupled to a side of a housing;
FIG. 13 is a bottom view of the device of FIG. 12, showing a microneedle array; and
FIG. 14 is an enlarged cross-sectional view taken along the line 14—14 in FIG. 12, showing a microneedle array and an internal chamber.
DETAILED DESCRIPTION OF THE
As can be seen from FIGS. 1-6, a first embodiment of a delivery device according to the present invention, which is designated generally by the reference numeral 10, comprises a housing 12 and a skin penetrating device 14. Housing 12 is dimensioned to contain a substance to be delivered to a patient and to be removably attached to the surface of the skin. Skin penetrating device 14 is associated with housing 12 to penetrate the skin of the patient and deliver the