Abstract:
A therapeutic treatment device, system and method for improving administration of a temperature sensitive drug into a tissue on the body of a patient at a drug injection site are disclosed. The device includes a treatment element with a controllable heating element in temperature communicative contact with the tissue adjacent to the drug injection site. The controllable heating element is configured to heat the tissue adjacent to the drug injection site to a controllable temperature but does not heat the injected drug above a predetermined limiting temperature, above which degradation of the injected drug may occur.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to U.S. Provisional Patent Application No. 61/112,463, filed Nov. 7, 2008, and entitled “Device And Method For Drug Delivery,” the disclosure of which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    In general, the present invention relates to systems and methods for delivering drugs to a patient. In particular, embodiments of the present invention relate to systems and methods for subcutaneous injection of a medicament and using one or more treatment sources to improve effectiveness of the injected drugs. 
       BACKGROUND OF THE INVENTION 
       [0003]    Drug injection by syringe, pen injectors and other devices are used regularly for subcutaneous injections of therapeutic fluids, drugs, proteins, and other compounds. Such delivery systems and methods are used also routinely for insulin delivery. In conventional insulin injection pens, the pen is typically configured to include a disposable insulin reservoir and a disposable needle through which insulin is injected into the tissue. The needle is for single use, while the insulin reservoir can be used for two to three days. 
         [0004]    In many instances, the patients require insulin injection around the clock to keep proper levels of glucose in their blood. Two major types of insulin can be injected—long-acting insulin that provides the basal insulin rate needed for keeping patient&#39;s blood glucose in the desired range between meals and over night and an insulin bolus injection that provides an amount of insulin for matching a dose of carbohydrates consumed by the patient during meals. 
         [0005]    When a patient consumes food, his or her levels of glucose rise. Unfortunately, many conventional subcutaneous injection devices are incapable of quickly matching or preventing the rise of blood glucose. The delay in such matching is also true in case of the “rapid-acting” insulin. Some of the reasons for this delay include a lag in the absorption of insulin from the injection site and the time it takes for complex insulin molecules to break down into monomers. 
         [0006]    Additionally, since blood glucose levels rise shortly following the meal, the delay in matching insulin to the rising levels causes post prandial hyperglycemic events (i.e., when levels of blood glucose are above normal) to occur. Further, occasionally after a certain period of time passes (e.g., 2-3 hours) after a meal, the blood glucose levels drop yet insulin concentrations in the blood rise followed by the peak of the systemic insulin effect and may result in causing hypoglycemic events (i.e., when levels of blood glucose are below normal) to occur. Both hyperglycemic and hypoglycemic events are highly undesirable. Additionally, since local blood perfusion at the insulin injection region has large variability, depending on the ambient temperature and other parameters, it induces large variations to the delay of the peak of time profile of the insulin action. Those variations in the insulin peak action period further increase the variability in the blood glucose level. 
         [0007]    Therefore, it is desirable to provide a system and a method that provides efficient and rapid injection and absorption of a drug to the patient circulatory system. In particular, it is desirable to provide a system and a method for injection of insulin to the patient that improves effectiveness of insulin in the blood to maintain normal levels of blood glucose and prevent or reduce hyperglycemic and hypoglycemic events. 
       SUMMARY OF THE INVENTION 
       [0008]    In some embodiments, the present invention relates to systems, devices and methods for injecting drug(s), substances and/or chemicals into a patient having a tissue treatment element for improving effectiveness of drug delivery upon injection. The device, according to some embodiments of the present invention, provides for a device for improving performance of drug delivery by injections. Optionally, some embodiments of the present invention provide for a device that further provides an additional treatment to a tissue region where the drug is delivered. The treatment can be utilized to improve drug delivery process by improving the drug&#39;s pharmacokinetic (“PK”) and/or pharmacodynamic (“PD”) profile. The treatment may include but is not limited to methods and devices described in PCT/IB2008/051049 and in PCT/IB2008/051044, disclosures of which are incorporated herein by reference in their entireties. Optionally, the treatment may come in various forms, for example, including an analgesic, vasodilator, or the like. Optionally, the treatment may be any form of treatment that leads to an improved vasodilatation of the tissue being injected, where the treatment, includes but is not limited to, exposing the tissue region to an energy, radiation, heat, mechanical vibrations, suction, massaging, acoustic stimulation, electrical stimulation, injection of an additional substance(s), or any combination of the above to improve drug&#39;s pharmacokinetic and/or pharmacodynamic profile. Each treatment type can be configured to have a separate protocol in order to evoke the necessary reaction such as vasodilatation or the like. 
         [0009]    In some embodiments, the applied treatment induces vasodilatation through neural stimulation of the tissue around the drug injection site. The neural stimulation can be induced by thermal stimulation. The human neural response to thermal stimulation includes several mechanisms such as the Nociceptive Axon Reflex that induce vasodilatation among other effects. 
         [0010]    In some embodiments, the induced neural response, such as the nociceptive axon reflex, also optionally induces widening of the capillary pores and increasing the capillary wall permeability. This effect is also significant for improving the absorption of the drag through the capillary wall. 
         [0011]    In some embodiments, the applied treatment may lead to a reduction in the variability of the drug absorption in the blood or lymph system and its local and systemic effects. For example, heating the tissue region in the vicinity of the area of drug delivery to a preset regulated temperature during and/or after the drug injection and absorption into the blood may cause local blood perfusion at that region to become more reproducible and the drug absorption process more uniform and reproducible as well. Also, by reducing the delay between drug injection into the tissue and absorption into the blood system, the variability of drug action induced by the delayed profile can be reduced. In some embodiments, the temperature of the region adjacent to the injection region can be regulated for longer periods, but the cost may be the energy source volume and weight. Thus, for minimization of the energy source size the heating period or heating temporal profile can be optimized in relation to the period of the drug injection and absorption into the blood. In some embodiments of the present invention, the treatment can be tuned according to the injected insulin dose and/or type. For instance, in case of heating the vicinity of the injection site the heating period for larger insulin dose can be longer to allow rapid absorption of the larger insulin dose. 
         [0012]    In some embodiments, a drug&#39;s temperature sensitivity can be accounted for so as to avoid protein denaturisation. In some embodiments, the delivered drug is insulin. Insulin is a temperature-sensitive protein. Thus, to avoid damage to insulin during the treatment protocol, heat can be limited so as to ensure efficacy of the delivered drug. The treatment protocol can be configured to control the temperature or the location of the treatment delivery site so as to not damage the drug. For instance, heating some types of insulin above 37° C. might damage it. Thus, the tissue around the injection site can be heated to induce the required neural response without heating the insulin itself above 37° C. For example heating the tissue at a distance of 10 mm around the injection site to 38.5° C. provides a significant vasodilatation without heating the injected insulin above 37° C. 
         [0013]    In some embodiments, the present invention relates to method and device for improving clinical outcome of IDDM patient by combining injection of rapid acting insulin analog with heating the skin at least 1 cm apart of the infusion site to 37-39° C. for a period of 30-60 min after the injection. This combination is be configured to provide a significant improvement of the insulin PK and PD without heating the injected insulin above 37° C. 
         [0014]    In some instances, instead of using rapid acting insulin, a mixed formulation (a mix of at least two insulin formulations with different absorption times, such as rapid acting insulin analog and regular insulin) can be used to provide both the fast absorption of the rapid acting insulin analog at the initial phase of the insulin absorption (such as 0-90 minutes from insulin injection) and then slower pharmacokinetics of the insulin action at the second phase of the insulin action (such as 90-200 min). This combination can be more beneficial, for instance, for fat reach meals in which the time that takes the food to be digested and the blood glucose excursion to diminish is longer. 
         [0015]    In some embodiments, the present invention relates to a therapeutic treatment device for improving administration of a temperature sensitive drug into a tissue on the body of a patient at a drug injection site. The device includes a treatment element with a controllable heating element in temperature communicative contact with the tissue adjacent to the drug injection site. The controllable heating element is configured to heat the tissue adjacent to the drug injection site to a controllable temperature but does not heat the injected drug above a predetermined limiting temperature, above which degradation of the injected drug may occur. 
         [0016]    In some embodiments, the present invention relates to a device for injection of a drug into a tissue on the body of a patient at a drug injection site. The device includes a housing for housing an injector for injecting the drug to an injection site, and a treatment element for providing an additional treatment at the drug injection site. 
         [0017]    In some embodiments, the present invention relates to a method for administering a temperature sensitive drug into a tissue on the body of a patient at a drug injection site using a treatment device including a treatment element having a controllable heating element. The method includes placing the treatment element in temperature communicative contact with tissue on the body of the patient; administering the drug to the tissue while applying treatment to the tissue; and controlling the temperature provided by the treatment element up to a predetermined maximum temperature to prevent heating the drug above a predetermined limiting temperature, above which degradation of the drug may occur. 
         [0018]    In some embodiments, the present invention relates to a method for treating a patient using a treatment device including a pen injector and a treatment element having a controllable treatment element. The method includes injecting a drug into a tissue on the body of the patient at a drug injection site using the pen injector; and using the treatment element, applying a treatment to the drug injection site before, during or after the injecting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    For a better understanding of the present invention, including the various objects and advantages thereof, reference is made to the following description, which is to be taken in conjunction with the accompanying illustrative drawings. 
           [0020]      FIG. 1  illustrates an exemplary system for delivering drugs to a patient having a treatment element, according to some embodiments of the present invention. 
           [0021]      FIG. 2  illustrates another exemplary system for delivering drugs to a patient having a heating pad, according to some embodiments of the present invention. 
           [0022]      FIG. 3  illustrates an exemplary heating pad, according to some embodiments of the present invention. 
           [0023]      FIG. 4  illustrates an exemplary kit including a system for delivering drugs to a patient, according to some embodiments of the present invention. 
           [0024]      FIG. 5  illustrates another exemplary system for delivering drugs to a patient having a flexible heating pad, according to some embodiments of the present invention. 
           [0025]      FIG. 6  illustrates another exemplary system for delivering drugs to a patient having a flexible heating pad, according to some embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0026]      FIGS. 1-6 , along with the following discussion, illustrate various exemplary embodiments of the present invention. As can be understood by one skilled in the art, the present invention is not limited to the embodiments illustrated in  FIGS. 1-6  and these figures are presented for discussion purposes only. 
         [0027]      FIG. 1  illustrates an exemplary drug delivery system, according to some embodiments of the present invention. In some embodiments of the present invention, the drug delivery system includes a treatment element that is configured to be a heating pad  1  used for four drug injections, as shown at  FIG. 1 . As can be understood by one skilled in the art, the number of drug injections or drug injection locations is not limited to four and can be any other number. The treatment element includes a processor and power source unit  2  (e.g., batteries) wired using electrical wires  16  to a heating element  15 . As shown in  FIG. 1 , reference numerals  10 - 13  on the heating pad indicate possible recommended locations for injection of four different drug injection occasions. Heating element  15  can be configured to include a heater to heat the tissue close and/or adjacent to an injection site  14  to a temperature that improves drug&#39;s pharmacokinetics and pharmacodynamics. In case of temperature sensitive drugs, such as insulin, heating element  15  can include a heater to heat the tissue around the injection site to a temperature that improves drug&#39;s pharmacokinetics and pharmacodynamics, without heating the drug above a limiting temperature that may degrade it, such as 37° C. in the case of some types of insulin. Heating pad  1  may also include an adhesive layer on its bottom side covered with a laminate before attachment to the body. In some embodiments, the heating pad can include a temperature sensor that provides temperature information to a processor to control the heating element to stabilize the heated tissue temperature to a required temperature. 
         [0028]    A more detailed illustration of an exemplary heating pad for four injections is shown at  FIG. 3 . In this embodiment, the heating pad includes a disposable unit  31  and a reusable unit  32  connected by an electrical connector. In some embodiments, the reusable unit  32  can be configured to include a processor and a rechargeable power source, a button  38  for starting heating and LED indicators  39  (for example, green and yellow colored LEDs). The disposable unit  31  includes heating element (not shown in  FIG. 3 ) and four reference numerals  33 - 36  indicating possible recommended locations for injections for four different drug injection occasions. 
         [0029]    The heating pad illustrated in  FIG. 3  can be used for example for one day of insulin injections. It can be attached to the abdomen or other locations used for insulin injections when the first injection should be taken. Before attachment to the body, the reusable part  32  is connected to the disposable unit  31 . In some embodiments, the patient can fold his skin at the injection site using the disposable unit  31 , which is flexible. The disposable unit  31  enables the patient to inject four injections at four different locations as some diabetes patients may be required to do. The possible recommended injection sites are marked by four reference numerals  33 - 36 , such that the injection is performed near one of the locations  33 - 36 . For instance, reference numeral  33  indicates that the insulin is injected near a skin location  37 . A typical procedure for insulin injection for both insulin syringes and insulin pens involves: (1) folding the skin between the thumb and the index finger of one hand, thereby raising the skin; (2) performing the injection into the folded raised skin using the other hand; and (3) after the injection, releasing the skin. This is done for safety purposes in order to prevent insulin injection into a location that is too deep in the body. Using the present invention&#39;s heating pad, this procedure can be implemented by (1) placing a thumb finger on the location indicated by reference numeral  33  and an index finger few centimeters below the reference numeral  33 ; (2) folding the skin between the fingers; (3) performing an injection into the skin between the thumb and index fingers; (4) releasing the skin after the injection. Reference numerals  33 - 36  can be indicated using numbers, different color markings, and/or names of meals, such as, breakfast, lunch dinner, supper, and/or in any other fashion. In some embodiments, a short time before or after the injection, the button  38  can be pressed by the patient to start the heating for a predetermined period of time and at a predetermined temperature profile. For instance, the device can perform heating for approximately 30 min to approximately 38.5° C. In some embodiments, the patient can start heating before injection (such as, 15 min prior to injection) to maximize the effect. In some embodiments, the controller can have a delay before starting the heating. After the heating ends, the patient can leave the heating pad attached until the next insulin injection is needed. In some embodiments, the heating pad further includes a temperature sensor for providing temperature information to a controller in the reusable part  32 . The temperature sensor is embedded in the disposable part  31  with good heat conduction to the heated tissue and/or to heating element. The sensor is further configured to be connected through the electrical connector to the reusable part  32 . In some embodiments, to reduce the cost of the disposable part  31 , the temperature sensor can be embedded in the reusable part  32  in heat communication with the heat conductive element disposed in the disposable part  31 . The temperature sensor can also be configured to measure temperature of the heated tissue with a good enough accuracy in order to control its temperature. In some embodiments, the heat conductive element can be a metal strip, such as copper, aluminum and/or any other suitable metal or combination thereof, disposed at the bottom of a disposable sticker with good heat conduction to the heated tissue and/or heating element. 
         [0030]    In some embodiments, the patient can detach the reusable part  32  from the disposable part  31 , which is kept adhered to the patient&#39;s body. In this embodiment, a smaller battery can be disposed inside the reusable part  32  for providing power for one injection. Thus, the size and weight of the reusable part  32  is reduced. In some embodiments, the battery disposed inside the reusable part  32  is capable of providing power for treatment of multiple injections (e.g., four injections, as shown in  FIG. 3 ). In some embodiments, when the reusable and disposable parts are connected, the controller is configured to perform a system test and transmit the results of the test to the user by lighting LED indicators  39  in a predetermined manner. For example, a green-lit LED indicator  39  indicates that the device is functioning normally and a yellow lit LED indicator  39  indicates that the heating pad/controller may be malfunctioning. In some embodiments, the LED indicators  39  can be used for indicating a heating operation (i.e., green lit LED is on), a low battery (i.e., a yellow lit LED is flashing), and any fault or misuse indication (i.e., yellow lit LED is on). 
         [0031]    In some embodiments, the heating pad can be configured to have an automatic operating cycle by identifying the timing of the injection and starting the heating profile accordingly. The injection detection can be performed by detecting folding of the skin using a pressure and/or mechanical sensor that can be placed in the disposable part  31  (shown in  FIG. 3 ). Alternatively, a pressure sensor can be placed at or on marking(s)/location(s) indicated by the reference numerals  33 - 36  (shown in  FIG. 3 ), which can be pressed during injection. Also, injection detection can be performed using a proximity detection of the injection device, such as, an injection pen or a syringe. In case of different markings on the disposable part  31  for different meals, the detection of the pressure on the marking related to a specific meal can indicate to the processor the type of meal is being consumed (e.g., breakfast, lunch, dinner, etc.), thereby causing the processor to invoke an appropriate heating profile that is optimized for the specific meal. Another alternative to get specific meal information is to add a real-time clock to the processing unit and use the time of the day information to decide upon the optimal treatment to apply. In some embodiments, disposable part  31  can have different markings according to meal contents, such as, carbohydrate-reach meal, fat-reach meal, etc., and the processor can be configured to identify the pressed marking and fit the optimal heat profile accordingly. In embodiments of meal-specific or meal-content-specific or dose-specific markings, various methods for indentifying the injection location can also be used to identify the injection location and to apply the optimal treatment accordingly. The proximity detection can be done also using RF detection by having RFID chip mounted on injection device, or optical detection or other methods known in the art. In some embodiments, the processor can be configured to alert the user in the event that the user attempts to inject insulin to a previously used injection site, such as, when the user presses the same marking on the disposable part  31  before the injection. The alert can be aural, visual and/or any other type or combination thereof, 
         [0032]    In some embodiments, a kit including components for carrying out various embodiments of the present invention can be provided. An example of this kit is illustrated at  FIG. 4 . Accordingly, in some embodiments, the kit can include an injection device and a plurality of treatment elements. For example, a case  41  can include an injection pen  46 , one more reusable units  42 - 46 , one more disposable units  47 , a space for needles  48  and a space for an additional vile(s) of insulin  49 . The patient can take this kit/case with her/him wherever s/he goes, thus, whenever s/he needs to get an insulin injection the kit/case contains everything necessary to carry out such injection. 
         [0033]    In some embodiments, the reusable unit&#39;s power source can be rechargeable and can be charged using the case  41 . For example, after completion of the treatment, the user can put the power source back into the case and into an electrical contact configured to charge the power source. In this embodiment, the case  41  can have a power source by itself for charging the reusable units  42 - 46 . The power source of the case  41  can also have a rechargeable battery, which can be charged during the nights (or at any other time) by placing the case  41  in a charging cradle for recharging or connecting a designated connector on the case to charger. 
         [0034]    In some embodiments, the case  41  can include several reusable units for a single injection (e.g., a single day use) and one or more for several injections (e.g., four injections). In some embodiments, the “reusable units” which can include the power source and controller, can be disposable as well. 
         [0035]      FIG. 2  illustrates another exemplary embodiment of a heating pad, which is similar to the one discussed above with regard to  FIG. 1 . The heating pad of  FIG. 2  includes a disposable part  21  and a reusable part  22 . The embodiment of the heating pad of  FIG. 2  is configured to perform injection using at least one of four “bays”  23 - 26  (or any other number or combination thereof) with the heating element disposed around each injection site. In some embodiments, the heating element can be configured to either partially or fully surround the respective injection site. In some embodiments, the heating can be applied to a larger portion of the heating site circumference. In some embodiments, the injection sites are provided in open areas (e.g., circles) which are fully embedded/within/inside the heating pad area similar to the circles  10 - 13  shown in  FIG. 1 . 
         [0036]      FIG. 5  illustrates another exemplary embodiment of the present invention, in which the injection sites are fully embedded within a flexible heating pad  54  area. The flexible heating pad  54  is configured to be connected to a reusable control unit  53 . Reference numerals  50  and  51  together indicate the location of an injection site  52 . Before injection, the patient may fold the skin between a thumb and an index finger of one hand located between reference numerals  50  and  51 , respectively, and perform injection procedure between the two fingers at the injection site  52 . 
         [0037]    In some embodiments, the disposable part may include identification and/or counting means and/or tracking means, such that the reusable unit can identify whether the disposable part was already used or how many times the disposable part has been used for heating the injection site. Additionally, such means can limit the number of times that the heating pad is used and prevent it from being used more than a preset number of times that the heating pad is capable of heating. It can have include an indication means to indicate that the heating pad can no longer be used for heating and/or an indication of the number of times that the heating pad can be operated. 
         [0038]    Such tracking means may include:
       a serial number, such as an EPROM chip, with a unique number that identifies the disposable part;   an RFID chip that uniquely identifies the disposable part;   an optical barcode that uniquely identifies disposable part;   a mechanical attachment in the reusable part for attachment to the disposable part that can be used only once (such that it breaks when they are disconnected, for example); and   a battery in the reusable part having enough energy for a limited preset number of usages.
 
The above illustrate non-limiting examples for modifying an electronic element (which is not disposable) and limiting the number of times it can be used before it has to be replaced. As can be understood by one skilled in the art, other ways to limit usage can be implemented.
       
 
         [0044]    An example for such identification mechanism is schematically shown in  FIG. 6 . In the shown embodiment, the disposable element  61  includes a RFID chip  62  with a unique identification code, which can be read by an RFID reader  63 , embedded in the reusable unit  64 . The reusable unit  64  can identify the disposable element  61  once they are connected using a unique code written inside the RFID chip  62 . The reusable unit stores this information inside a memory element, such as a non-volatile memory element. Each time the disposable element is used the information is written as well in the memory element. This way the reusable treatment element can count how many times the disposable part has been used for heating the injection site. Using that information, it can limit the number of times that the heating pad is used and prevent it from being used more than a preset number of times that the heating pad is capable of heating. The reusable unit  64  can include an indication means to indicate that the heating pad can no longer be used for heating, such as a red LED indicator  65  and/or an indication of the number of times that the heating pad can be operated, such as LED bar or numeric display (not shown). 
         [0045]    In some embodiments, the disposable part includes a set of fuse-type conductive elements which can be manufactured together with the heating element using the same process, such as by conductive printing, PCB etching, or other known, and/or low cost manufacturing methods. The fuse-type conductive element can be produced by printing a short very narrow conductive element. For each use, the reusable part burns one fuse element by applying a short high electrical current signal to that element. Thus, the reusable unit can determine whether all fuse elements have been burned out and thus, whether the disposable part can be used again. These mechanisms provide an additional safety protection such that the disposable part will not be used beyond a predetermined number of injections and may be damaged, or influence the heating accuracy or the contact to the tissue. 
         [0046]    In some embodiments, different numbers of injections are supported by the heating pad, such as a single use for a single injection or all the injections of few days, such as 3 days. In some embodiments, the reusable part has a real time clock that provides time and date and limits the use of each disposable unit for a given period, such as 1 day of use, without limiting the number of injections or treatment given at that period. 
         [0047]    In some embodiments, the reusable part of the heating pad includes a timer or is in wireless communication with a timer that is used to remind the user of the timing for the next injection. Each time the injection is used, the timer is reset. This feature can provide the user with a reminder to perform an injection and prevent the user from repeated injections. 
         [0048]    In some embodiments, the reusable and disposable parts can include means for detecting a volume of the injected subcutaneous drug stored in a depot and adjusting the tissue treatment (e.g., an amount of the drug being injected) according to that measurement. This can be achieved, for example, by adding an electrode to the disposable part which can be used for electrical impedance measurement and having in the reusable part electronics and a controller to support the impedance measurement. Once the drug is infused to the subcutaneous tissue, it alters the impedance measurement result and as it clears from the depot the impedance measurement returns to the baseline. Thus, by tracking the impedance measurement, the device can detect the clearance of the drug from the subcutaneous depot and the treatment to the tissue can be adjusted accordingly. For example, the treatment can depend on the volume of the drug depot as well as on the velocity by which the drug clears from the depot so that when the depot is cleared the treatment stops or if the clearance velocity is low the treatment can be increased. 
         [0049]    Thus, it is seen that devices, systems and methods for improving the effectiveness of drug delivery upon injection are provided. Although particular embodiments have been disclosed herein in detail, this has been done by way of example for purposes of illustration only, and is not intended to be limiting with respect to the scope of the appended claims, which follow. In particular, it is contemplated by the applicant that various substitutions, alterations, and modifications may be made without departing from the spirit and scope of invention as defined by the claims. Other aspects, advantages, and modifications are considered to be within the scope of the following exemplary claims. The claims presented are representative of at least some of the inventions disclosed herein. Other, unclaimed inventions are also contemplated. Applicants reserve the right to pursue such inventions in later claims.