Patent Application
20220378693
It is provided a method and device for delivering transdermally a molecule non-invasively to a subject comprising irreversibly electroporating a region of the skin.
Delivery of drugs through the skin has always been a challenging area for research due to the barrier properties that exhibit the outermost layer of skin stratum corneum. In the last two decades, transdermal drug delivery systems have been developed and proven to offer significant clinical benefits over other dosage forms or formulations. Because transdermal drug delivery offers controlled as well as predetermined rate of release of a drug into the patient, it represents a mean able to maintain steady state blood and systemic concentration. Transdermal delivery avoids the stomach environment where the drug can be degraded and the first pass effect where active drug molecules can be converted to inactive molecules or even to molecules responsible for side effects. Transdermal drug delivery provides a mean to a steady concentration in plasma and/or the interstitial fluid and potentially the drug input can be stopped at any point after removal of the device allowing the delivery from the site. Developing means for delivering drug transdermally could also increase compliance and reduce medical costs, improve bioavailability, and represent a favorable route of administration for pediatric patients. It is also predicted that transdermal delivery can decrease chances of overdose (see Sachan and Bajpai, International Journal of Research and Development in Pharmacy and Life Sciences, December, 2013, 3(1): 748-765, Marwah et al., Drug Deliv, 2016, 23(2): 564-578).
Since the first transdermally delivered drug, Transderm Scop®, a transdermal patch delivering scopolamine, introduced by Novatris in 1979, innovations in transdermal delivery systems can be classified according to three stages of development. A first generation of systems were developed consisting of patches to deliver drugs that can cross the skin at acceptable therapeutic levels. In almost all transdermal patch models, the drug is stored in a reservoir that is enclosed between two different membranes. The first membrane which is in contact with the outside consists of an impermeable membrane and which may have an adhesive layer at its ends to allow adhesion of the patch to the skin. The second membrane which is in contact with the skin consists of a semi-permeable membrane which can serve as a barrier limiting the rate of transfer of the drug. Some first-generation patch models contain a drug dissolved in a liquid or a gel-based reservoir. These patches are characterized by four layers: an impermeable backing membrane, a drug reservoir, a semipermeable membrane that can act as a barrier limiting the rate of transfer of the drug and an adhesive layer. Other first-generation patches are characterized by the presence of the drug to be delivered in a solid polymer matrix. In this same generation, three-layered patches can be noted, eliminating the semi-permeable membrane or two layers, incorporating the drug directly into the adhesive.
A second generation of systems were developed to promote the distribution of small molecules by increasing the skin's permeability and driving forces for transdermal transport. The second generation of transdermal delivery systems can be recognized as those that have begun to improve skin permeability by using chemical permeation enhancers (CPEs) to widen the spectrum of possibly transdermally applicable molecules. However, the methods used such as conventional chemical enhancers, non-cavitational ultrasound and iontophoresis have generally failed to balance the increased permeability of the stratum corenum and to protect the deeper tissues from damage caused by these same methods.
A third generation of transdermal delivery systems, mainly targeting the stratum corenum, is now in development. This approach enables almost complete disruption of the stratum carenum wall and thereby more effectively deliver molecules transdermally. Novel chemical enhancers, ultrasound, electroporation and more recently microneedles, causing thermal ablation and microdermabrasion have been shown to deliver macromolecules, including vaccines and therapeutic proteins, across the stratum corenum in human clinical trials.
There is thus still a need to be provided with means for transdermally deliver a drug or molecule to a patient.
One aim of the present disclosure is to provide a method for delivering transdermally a molecule non-invasively to a subject comprising the steps of irreversibly electroporating a region of the skin without generating any heat; applying a pressure at or near the region of the skin being irreversibly electroporated, the combination of irreversibly electroporating the skin and periodically applying the pressure forming openings in the skin; and delivering the molecule through the openings.
In an embodiment, a non-pulsed voltage and a pulsed voltage are generated between at least a first moving or stationary electrode and a second stationary electrode for electroporating the skin.
In another embodiment, the pressure is periodically pulsed or continuous.
In a further embodiment, the pressure applied at or near the region of the skin being electroporated is or is not monitored by a pressure sensor.
In a further embodiment, the subject is an animal or a human.
In another embodiment, the molecule is a drug, an antibody, a DNA molecule, a RNA molecule, a virus, an enzyme or a cell.
In an additional embodiment, the molecule is scopolamine, nitroglycerin, clonidine, estradiol, fentanyl, nicotine, testosterone, lidocaine, epinephrine, estradiol, norethindrone, ethinylestradiol, oxybutynin, tetracaine, methylphenidate, selegiline, retigabine, rivastigmine, AB-1001, acyclovir, buprenorphine, fertility hormone, granisetron, heat-labile enterotoxin of E. coli., human growth hormone, influenza vaccine, insulin, ketoprofen, parathyroid hormone, sufentanil, and/or triamcinolone acetonide, catalase, peroxidase, dismutase or a combination of the last three enzymes.
In another embodiment, the method provided herein further comprises delivering the molecule through a transfer limiting membrane controlling the rate of administration of the molecule to the openings.
It is also provided that the molecule to be delivered is dissolved in an aqueous, or a neutral or a lipophilic solution containing also a CPE, or in a gel, or in a cream or an ointment containing also a CPE. The chemical permeation enhancers (CPEs) as encompassed herein provides a mean to maintain the opened region of the skin open.
It is also provided a device for non-invasively delivering transdermally a molecule to a subject comprising means for irreversibly electroporating the skin by generating a non-pulsed voltage and a pulsed voltage between at least one first moving or stationary electrode and a second stationary electrode; a vacuum pump for periodically providing a pressure above the skin; and a chamber comprising the molecule to be delivered.
In an embodiment, at least one first and second electrodes are contained in the chamber.
In a further embodiment, the chamber is a separate part from the first and second electrodes used for the electroporation.
In another embodiment, the device described herein further comprises a sensor or a plurality of sensors for analyzing the delivery rate of the molecule and/or the temperature of the subject.
In an embodiment, the sensor or a plurality of sensors further comprise a wired or wireless communication device.
In another embodiment, the device further comprises an adhesive means for fixing the device on the skin of the subject.
In an embodiment, the vacuum pump is a peristaltic pump, a diaphragm pump, or a piston pump.
In another embodiment, the pressure generated by the vacuum pump is from about 2 kPa to about 98 kPa.
In an embodiment, the vacuum generated by the pump is pulsed or continuous.
In another embodiment, the device further comprises a transfer limiting membrane for controlling the rate of administration of the molecule.
Reference will now be made to the accompanying drawings, showing by way of illustration, a preferred embodiment thereof.
It will be noted that throughout the appended drawings, like features are identified by like reference numerals.
It is provided a method for delivering transdermally a molecule non-invasively to a subject comprising the steps of irreversibly electroporating a region of the skin without generating any heat; applying for a short period of time a pressure at or near the region of the skin being irreversibly electroporated, the combination of irreversibly electroporating the skin and applying the pressure for a short period of time forming openings in the skin; and delivering the molecule through the openings.
Accordingly, it is described a method and a device to overcome the barrier of the epidermis and especially the stratum carenum. Once the breakdown of this barrier is realized by the method and the device proposed hereinafter, any kind of drug regardless of its size, regardless of its hydrophobic/hydrophilic/neutral/lipophilic character will pass through this barrier and reach the dermis and hence be available locally or to the systemic circulation in the target body.
Disclosed herein is a method which creates one or more electrophilic conduit through the stratum corneum. These openings are permanent and have a duration limited only by the duration of the treatment. Otherwise, as long as these openings or conduits through the stratum corneum are in contact with the drug to be transferred to the general circulation, they will remain open and close only after removing the contact between them and the drug in question.
The device and a method as described in the Canadian patent No. 2655017, incorporated by reference herewith in its entirety, can be used to irreversibly form one or a plurality of openings or conduits solely through the stratum corneum. The conduit(s) hence formed will be the area of interest where a target molecule(s) present in a chemical composition or standing alone will be placed to reach the systemic circulation through its transport in the interstitial fluid present in the dermis and underneath the dermis.
In an embodiment, the device used herein can comprise a sensing electrode as illustrated in
It is described herein, measurement of an electrical parameter generated when a single frequency of an alternative voltage with a sinusoidal amplitude comprised between 2 to 60 mV is superimposed to the sensing electrode maintained at a DC voltage which corresponds to the rest voltage or the open circuit voltage of the electrochemical cell (impedimetric sensor). Such electrical parameters might include the variation of the values of the impedance (from Nyquist plot:
The electrical elements or network as described herein (see
The Nyquist plot obtained when an alternative voltage with a sinusoidal amplitude comprised between 2 to 60 mV is superimposed to the sensing electrode is maintained at a DC voltage corresponding to the rest voltage or the open circuit voltage of the electrochemical cell (impedimetric sensor) in agreement with the electrical equivalent circuit shown in
Electroporation of the skin is affected by the amplitude of the applied voltage, the shape of the applied voltage and of the electrodes, the frequency of the applied signal, the intensity of the applied current and the duration of the applied signal. The amplitude of the applied voltage is expressed in volts and can vary from 5 V to 500 V depending on the above variables and it is now not independent on the distance between the positive and the negative electrodes if this distance is comprised between 1 to 10 cm. The frequency of the applied voltage may vary from 50 μS to 7000 μS. The shape of the signal is preferred to be square but other types of signal can be used. The preferred duration is less than three minutes depending on the above cited variables, but duration above the preferred value or under the preferred value is not excluded.
As encompassed herein, the term “irreversibly” is intended to describe real conduits formed through the stratum corneum. These conduits last as long as the target molecule is in contact with them. These conduits have real physical dimensions such as a diameter and a depth. They are note reversible.
The openings or conduits formed when the method described herein and is applied is intended to mean micro-holes through the stratum corneum formed following a short and controlled irreversible-electroporation as described herein (as seen in
More particularly, the device encompassed herein comprises means for electroporating the skin by generating a non-pulsed voltage and a pulsed voltage, and a sensor which are controlled electronically. The analysis of the signal obtained from the sensor in order to transform the information and to send the information to an alarm or a cell phone, for example, for further diffusion of the obtained information, is also controlled electronically. The irreversibly electroporation described herein of a region of the skin is done without generating any heat to preserve the connective tissue, in order to not denature molecules and collagen, eliminating any injuries to the cell scaffold and does not compromise the blood vessel matrix, which results in a clear margination of treated and nontreated areas.
As described in Canadian patent No. 2655017 the chamber for example used during the electroporation and sensing steps comprises electrodes, and more specifically, a reference electrode, a sensing electrode, and a counter electrode. Connection pads can be used to connect the electrodes to the electronic part of the device.
An embodiment of the chamber of the device encompassed herein is illustrated in
The chamber comprises at least one hole 1 to receive a screw 19, a body 3 of the chamber is made of a polymer body 2 with holes 4, wherein negative solid electrodes passes through said holes 4 to be in contact with the skin. A thin layer membrane 5 of 50 to 200 μm is used to keep the skin in place and to avoid its suction. A further thicker membrane 5′ of 2 to 5 mm is used to separate the different mini-chamber.
As seen in
The chamber 21 can be made completely from a polymeric material, a combination of a polymeric material or any other material that are electrically non-conductive or insulating.
As seen in
The device can be covered by a material such as a capsule or an adhesive in order to facilitate its use, particularly in a situation where a liquid can surround the chamber 21. The chamber 21 can include a sealed hole. Furthermore, in order to increase the fixture of the chamber 21 as described herein, a non-allergenic material such as a strap can be used to stabilize the contact between the device and the skin.
Before the application of the chamber 21 on the skin, the skin can be gently cleaned by any known chemicals used in medicine to clean such skin or simply using a soap and/or water. Preferably, any chemicals that evaporate after cleaning are used such that they do not leave any residue at the surface of the skin. Moreover, the chemicals or the soap should not induce any allergenic reaction of the skin nor modify the structure of the skin. Furthermore, in some cases the use of Povidone-iodine (PVP-I), also known as iodopovidone must be used for skin disinfection before the electroporation and the installation of the chamber 21. As soon as the skin is gently cleaned or preferably disinfected, the chamber 21 is attached on the top of the cleaned or disinfected skin by the help of the non-allergenic material such as the adhesive 26 or the strap or bracelet (
The molecule can be delivered for example through a micros conduit within the chamber 21. The chamber 21 may or may not be isolated from a pump for example by a check valve or a one-way valve. The administration can be carried out by the application of a controlled pressure that is applied in the conduit system comprised namely of the chamber 21. The controlled pressure is maintained by the action of the pump and the level of the pressure is continuously monitored and controlled using a pressure sensor or pressure switch, which could be located before or after the check valve.
The pressure is attained by activating the pump in an on/off fashion or in a continuously modulated fashion. The actual value of the pressure can be controlled using the pressure sensor or a pressure switch. The pump and the pressure sensor can be under the control of a microcontroller that shall continuously or discontinuously monitor the actual pressure in the device from reading the actual status of the pressure sensor or the pressure switch and shall accordingly activate or deactivate the operation of the pump in a continuous, discontinuous or modulated fashion in order to achieve the desired pressure. A temperature sensor can also be incorporated in order to improve the efficiency of the device. Furthermore, for example, a flow sensor could be installed between the outlet of the chamber 21 and the pump in order to inform the user that the administration process is going well.
The vacuum and overpressure are generated periodically inside the chamber 21 between the skin and the pump in order to improve the adhesion and the administration. Preferably, the vacuum pump can provide a vacuum that will provide enough suction to stretch the portion of the skin in the region from which the molecule is to be administered. As the suction provided by the vacuum pump is stretching the appropriate portion of the skin, the suction provided by the vacuum pump also causes the stretched portion. A vacuum pump that is suitable for the device defined herein can be a peristaltic pump, a diaphragm pump, a piston pump, a rotary vane pump, or any other pump that will perform the required functions set forth previously. Typically, the vacuum pump preferably employs a self-contained permanent magnet DC motor. Vacuum pumps that are suitable for this invention are well-known to those of ordinary skill in the art and are commercially available. The vacuum pump is preferably capable of providing a differential pressure down to about 0.90 atm, and is more preferably operated at from about 0.99 atm and 0.2 atm. The vacuum provided by the vacuum pump can be continuous or pulsed. It is preferred that the applied vacuum does not cause irreversible damage to the skin. It is preferred that the applied vacuum does not produce bruises and discolorations of the skin that persist for several weeks. It is also preferred that the level of applied vacuum and the duration of application of the vacuum do not be so excessive that it causes the dermis to separate from the epidermis, which results in the formation of a blister filled with fluid.
The irreversible electroporation of the skin is carried out by the application of a pulsed voltage between two electrodes or a plurality of electrodes forming a network of electrodes. As an illustration of the art herein, the excitation part of the process is carried out using at least two electrodes placed in contact with the exposed portion of the skin which is the negative electrode and the positive electrode which is used also as an adhesive. One of the excitation electrodes (negative electrode or electroporating electrode) is maintained in contact with the exposed portion of the skin during the non-heating irreversible electroporation.
Electroporation of the skin is affected by the amplitude of the applied voltage, the shape of the applied voltage and of the electrodes, the frequency of the applied signal and the duration of the applied signal. The amplitude of the applied voltage is expressed in volts and can vary from 0.100 V to 500 V depending on the above variables and the distance between the electrodes. The frequency of the applied voltage may vary from 100 μ-Second to 10 m-Second. The shape of the signal is preferred to be square but other type of signal can be used. The preferred duration is less than a second depending on the above cited variables, but duration above the preferred value or under the preferred value is not excluded.
Herein, irreversible electroporation is an event in which microsecond electrical pulses are applied on a living or non-living tissue, wherein the tissue is illustrated by the epidemies of a living subject, destabilizing the electrical potential across the tissue and resulting in irreversible nanoscale/microscale pores. Accordingly, to avoid the non-desirable Joule's effect or the generation of heat the electrical parameters are chosen such that the cell membrane is selectively targeted without inducing thermal damage to the rest of the tissue. These parameters are illustrated hereafter in Table 1.
Due to its nonheating nature, the irreversible electroporation described herein does not affect the connective tissue nor does it denature molecules and collagen, eliminating any injuries to the cell scaffold and does not compromise the blood vessel matrix, and that the irreversible electroporation results in a clear margination of treated and nontreated areas.
Disclosed herein is a method that transfer an exogenous molecule or a plurality of molecules which have a therapeutic effect on the target subject or influence the wellbeing of the subject or have preventive actions on the subject, or have an improvement effect on the health of the subject. Herein the subject could be a human regardless of his age or an animal.
In an embodiment, the molecule or plurality of molecules having a therapeutic effect can be at least one of scopolamine, nitroglycerin, clonidine, estradiol, fentanyl, nicotine, testosterone, lidocaine, epinephrine, estradiol, norethidrone, ethinylestradiol, oxybutynin, tetracaine, methylphenidate, selegiline, rotigotine, rivastigmine, AB-1001, acyclovir, buprenorphine, fertility hormone, granisetron, heat-labile enterotoxin of E. coli., human growth hormone, influenza vaccine, insulin, ketoprofen, parathyroid hormone, sufentanil, and/or triamcinolone acetonide, which are all drugs/molecules which have been administered by a transdermal mean.
Disclosed herein is an exogenous molecule or a plurality of molecules that could be used alone and could be a solid substance which has an excellent solubility in the interstitial fluid, could be a liquid which is preferably miscible in the interstitial fluid, could be in the form of a lyophilized molecule or could be in the form of a particle.
As encompassed herein, the exogenous molecule or plurality of molecules could have the molecular weight of a small ion such as lithium ion and could have a heavy weight such as a DNA or even heavy molecules such as a pathogen or a virus. Also encompassed is that the exogenous molecule or plurality of molecules described could be enclosed in a solid polymeric matrix, could be a part of an emulsion, could be dissolved in aqueous liquid, lipophilic liquid, could be enclosed in the form of an ointment based mixture, a gelatinous mixture, a solid solution or a powder mixture. The exogenous molecule or a plurality of molecules can also be dissolved before its use in the extracted interstitial fluid of the subject.
In an embodiment, it is disclosed that the method and devices encompassed herein include a transfer limiting membrane between the skin and the target molecule or a plurality of molecules to be transferred. This transfer limiting membrane will have solely the role to maintain a determined transfer rate of the target molecule or a plurality of molecules and may contain an enhancer which will have solely the role to maintain the micro-conduit(s) opened.
When the target molecule or the plurality of molecules are a biological substance such as an enzyme, a protein, an antibody for example, a stabilizer such as the human serum albumin will be added to the formulation of the substrate where the target molecule or the plurality of molecules will be encapsulated.
In an embodiment, the target molecule or plurality of molecules may include, as an example but not limited to, methylphenidate, superoxide dismutase or a mimetic of superoxide dismutase, catalase, amorphous insulin and testosterone.
In another embodiment, the method and devices described herein may include a miniature temperature sensor such as a miniature RTD, a miniature thermistor or a miniature thermocouple. The miniature temperature sensor will have solely the role to inform the user or to automatically put an end to the transfer of the exogenous molecule or the plurality of molecules to the dermis if an increase of temperature or sweat or a combination of both present a risk of an over dose.
While the disclosure has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations, including such departures from the present disclosure as come within known or customary practice within the art, and as may be applied to the essential features hereinbefore set forth, and as follows in the scope of the appended claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CA2020/051415 | 10/22/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62925340 | Oct 2019 | US |
