Patent Grant
11285274
This disclosure relates to droplet delivery devices and more specifically to droplet delivery devices for the delivery of fluids to the pulmonary system.
The use of aerosol generating devices for the treatment of a variety of respiratory diseases is an area of large interest. Inhalation provides for the delivery of aerosolized drugs to treat asthma, COPD and site-specific conditions, with reduced systemic adverse effects. A major challenge is providing a device that delivers an accurate, consistent, and verifiable dose, with a droplet size that is suitable for successful delivery of medication to the targeted lung passageways.
Dose verification, delivery and inhalation of the correct dose at prescribed times is important. Getting patients to use inhalers correctly is also a major problem. A need exists to insure that patients correctly use inhalers and that they administer the proper dose at prescribed times. Problems emerge when patients misuse or incorrectly administer a dose of their medication. Unexpected consequences occur when the patient stops taking medications, owing to not feeling any benefit, or when not seeing expected benefits or overuse the medication and increase the risk of over dosage. Physicians also face the problem of how to interpret and diagnose the prescribed treatment when the therapeutic result is not obtained.
Currently most inhaler systems such as metered dose inhalers (MDI) and pressurized metered dose inhalers (p-MDI) or pneumatic and ultrasonic-driven devices generally produce drops with high velocities and a wide range of droplet sizes including large droplet that have high momentum and kinetic energy. Droplets and aerosols with such high momentum do not reach the distal lung or lower pulmonary passageways but are deposited in the mouth and throat. As a result, larger total drug doses are required to achieve the desired deposition in targeted areas. These large doses increase the probability of unwanted side effects.
Aerosol plumes generated from current aerosol delivery systems, as a result of their high ejection velocities and the rapid expansion of the drug carrying propellant, may lead to localized cooling and subsequent condensation, deposition and crystallization of drug onto the ejector surfaces. Blockage of ejector apertures by deposited drug residue is also problematic.
This phenomenon of surface condensation is also a challenge for existing vibrating mesh or aperture plate nebulizers that are available on the market. In these systems, in order to prevent a buildup of drug onto mesh aperture surfaces, manufacturers require repeated washing and cleaning, as well as disinfection after a single use in order to prevent possible microbiological contamination. Other challenges include delivery of viscous drugs and suspensions that can clog the apertures or pores and lead to inefficiency or inaccurate drug delivery to patients or render the device inoperable. Also, the use of detergents or other cleaning or sterilizing fluids may damage the ejector mechanism or other parts of the nebulizer and lead to uncertainty as to the ability of the device to deliver a correct dose to the patient or state of performance of the device.
Accordingly, there is a need for an inhaler device that delivers particles of a suitable size range, avoids surface fluid deposition and blockage of apertures, with a dose that is verifiable, and provides feedback regarding correct and consistent usage of the inhaler to patient and professional such as physician, pharmacist or therapist.
In one aspect, the disclosure relates to a method for the systemic delivery of a therapeutic agent as an ejected stream of droplets in a respirable range to the pulmonary system of a subject for the treatment of a disease, disorder or condition. The method may comprise: (a) generating an ejected stream of droplets via a piezoelectric actuated droplet delivery device, wherein at least about 70% of the ejected stream of droplets have an average ejected droplet diameter of less than about 5 μm; and (b) delivering the ejected stream of droplets to the pulmonary system of the subject such that at least about 70% of the mass of the ejected stream of droplets is delivered in a respirable range to the pulmonary system of a subject during use to thereby systemically delivery the therapeutic agent to the subject to treat the disease, disorder or condition.
In other aspects, the disease, disorder or condition is selected from diabetes mellitus, rheumatoid arthritis, plaque psoriasis, Crohn's disease, hormone replacement therapy, neutropenia, nausea, and influenza. In further aspects, the therapeutic agent is a therapeutic peptide, protein, antibody, or other bioengineered molecule. In yet further aspects, the therapeutic agent is selected from growth factors, insulin, vaccines, antibodies, Fc-fusion protein, hormones, enzymes, gene therapies and RNAi cell therapies, antibody-drug conjugates, cytokines, anti-infective agents, polynucleotides, oligonucleotides, or any combination thereof. In other aspects, the therapeutic agent is delivered to the pulmonary system of the subject at a reduced dosage, as compared to oral or intravenous dosages.
In further aspects, the ejected stream of droplets are subjected to an approximate 90 degree change of trajectory within the piezoelectric actuated droplet delivery device such that droplets having a diameter greater than about 5 μm are filtered from the ejected stream of droplets due to inertial forces, without being carried in entrained airflow through and out of the piezoelectric actuated droplet delivery device to the pulmonary system of the subject. The filtering of droplets having a diameter greater than about 5 μm may increase the mass of the ejected stream of droplets delivered to the pulmonary system of the subject during use. In further aspects, the ejected stream of droplets is delivered over a period of time less than about 2 seconds.
In other aspects, the piezoelectric actuated droplet delivery device may comprise: a housing; a reservoir disposed within or in fluid communication with the housing for receiving a volume of fluid; an ejector mechanism in fluid communication with the reservoir, the ejector mechanism comprising a piezoelectric actuator and an aperture plate, the aperture plate having a plurality of openings formed through its thickness and the piezoelectric actuator operable to oscillate the aperture plate at a frequency to thereby generate an ejected stream of droplets; and at least one differential pressure sensor positioned within the housing, the at least one differential pressure sensor configured to activate the ejector mechanism upon sensing a pre-determined pressure change within the housing to thereby generate an ejected stream of droplets.
In yet other aspects, the aperture plate of the piezoelectric actuated droplet delivery device comprises a domed shape. The piezoelectric actuated droplet delivery device may further comprise a laminar flow element located at the airflow entrance side of the housing and be configured to facilitate laminar airflow across the exit side of aperture plate and to provide sufficient airflow to ensure that the ejected stream of droplets flows through the droplet delivery device during use.
In another aspect, the disclosure relates to a piezoelectric actuated droplet delivery device for delivering a fluid as an ejected stream of droplets to the pulmonary system of a subject. The droplet delivery device may include: a housing; a reservoir disposed within or in fluid communication with the housing for receiving a volume of fluid; an ejector mechanism in fluid communication with the reservoir, the ejector mechanism comprising a piezoelectric actuator and an aperture plate, the aperture plate having a plurality of openings formed through its thickness and the piezoelectric actuator operable to oscillate the aperture plate at a frequency to thereby generate an ejected stream of droplets, at least one differential pressure sensor positioned within the housing; the at least one differential pressure sensor configured to activate the ejector mechanism upon sensing a pre-determined pressure change within the housing to thereby generate an ejected stream of droplets; the ejector mechanism configured to generate the ejected stream of droplets wherein at least about 70% of the droplets have an average ejected droplet diameter of less than about 5 microns, such that at least about 70% of the mass of the ejected stream of droplets is delivered in a respirable range to the pulmonary system of a subject during use.
In certain aspects, the droplet delivery device further includes a surface tension plate between the aperture plate and the reservoir, wherein the surface tension plate is configured to increase contact between the volume of fluid and the aperture plate. In other aspects, the ejector mechanism and the surface tension plate are configured in parallel orientation. In yet other aspects, the surface tension plate is located within 2 mm of the aperture plate so as to create sufficient hydrostatic force to provide capillary flow between the surface tension plate and the aperture plate.
In yet other aspects, the aperture plate of the droplet delivery device comprises a domed shape. In other aspects, the aperture plate is composed of a material selected from the group consisting of poly ether ether ketone (PEEK), polyimide, polyetherimide, polyvinylidine fluoride (PVDF), ultra-high molecular weight polyethylene (UHMWPE), Ni, NiCo, Pd, Pt, NiPd, metal alloys, and combinations thereof. In other aspects, one or more of the plurality of openings of the aperture plate have different cross-sectional shapes or diameters to thereby provide ejected droplets having different average ejected droplet diameters.
In some aspects, the droplet delivery device further includes a laminar flow element located at the airflow entrance side of the housing and configured to facilitate laminar airflow across the exit side of aperture plate and to provide sufficient airflow to ensure that the ejected stream of droplets flows through the droplet delivery device during use. In other aspects, the droplet delivery device may further include a mouthpiece coupled with the housing opposite the laminar flow element.
In other aspects the ejector mechanism of the droplet delivery device is orientated with reference to the housing such that the ejected stream of droplets is directed into and through the housing at an approximate 90 degree change of trajectory prior to expulsion from the housing.
In yet other aspects, the reservoir of the droplet delivery device is removably coupled with the housing. In other aspects, the reservoir of the droplet delivery device is coupled to the ejector mechanism to form a combination reservoir/ejector mechanism module, and the combination reservoir/ejector mechanism module is removably coupled with the housing.
In other aspects, the droplet delivery device may further include a wireless communication module. In some aspects, the wireless communication module is a Bluetooth transmitter.
In yet other aspects, the droplet delivery device may further include one or more sensors selected from an infer-red transmitter, a photodetector, an additional pressure sensor, and combinations thereof.
In a further aspect, the disclosure relates to a breath actuated droplet delivery device for delivering a fluid as an ejected stream of droplets to the pulmonary system of a subject. The device may include: a housing; a combination reservoir/ejector mechanism module in fluid communication with the housing for receiving a volume of fluid and generating an ejected stream of droplets; the ejector mechanism comprising a piezoelectric actuator and an aperture plate comprising a domed shape, the aperture plate having a plurality of openings formed through its thickness and the piezoelectric actuator operable to oscillate the aperture plate at a frequency to thereby generate the ejected stream of droplets; at least one differential pressure sensor positioned within the housing; the at least one differential pressure sensor configured to activate the ejector mechanism to generate the ejected stream of droplets upon sensing a pre-determined pressure change within the housing when a subject applies an inspiratory breath to an airflow exit side of the housing; the ejector mechanism configured to generate the ejected stream of droplets wherein at least about 70% of the droplets have an average ejected droplet diameter of less than about 5 microns, such that at least about 70% of the mass of the ejected stream of droplets is delivered in a respirable range to the pulmonary system of the subject during use.
In other aspects, the domed-shape aperture plate of the breath actuated droplet delivery device is composed of a material selected from the group consisting of poly ether ether ketone (PEEK), polyimide, polyetherimide, polyvinylidine fluoride (PVDF), ultra-high molecular weight polyethylene (UHMWPE), Ni, NiCo, Pd, Pt, NiPd, metal alloys, and combinations thereof.
In other aspects, the breath actuated droplet delivery device further includes a laminar flow element located at an airflow entrance side of the housing and configured to facilitate laminar airflow across the exit side of aperture plate and to provide sufficient airflow to ensure that the ejected stream of droplets flows through the droplet delivery device during use. In yet other aspects, the breath actuated droplet delivery device further includes a mouthpiece coupled with the housing opposite the laminar flow element.
In a further aspect, this disclosure relates to a method of filtering large droplets from an aerosolized plume using inertial forces. The method may include: generating an ejected stream of droplets using a droplet delivery device, wherein the ejector mechanism is orientated with reference to the housing such that the ejected stream of droplets is directed into and through the housing at an approximate 90 degree change of trajectory prior to expulsion from the housing; and wherein droplets having an diameter greater than about 5 μm are deposited on the sidewalls of the housing due to inertial forces, without being carried in entrained airflow through and out of the droplet delivery device to the pulmonary system of the subject.
The invention will be more clearly understood from the following description given by way of example, in which:
Effective delivery of medication to the deep pulmonary regions of the lungs through the alveoli, has always posed a problem, especially to children and elderly, as well as to those with the diseased state, owing to their limited lung capacity and constriction of the breathing passageways. The impact of constricted lung passageways limits deep inspiration and synchronization of the administered dose with the inspiration/expiration cycle. For optimum deposition in alveolar airways, particles with aerodynamic diameters in the ranges of 1 to 5 μm are optimal, with particles below about 4 μm shown to reach the alveolar region of the lungs, while larger particles are deposited on the tongue or strike the throat and coat the bronchial passages. Smaller particles, for example less than about 1 μm that penetrate more deeply into the lungs have a tendency to be exhaled.
In certain aspects, the present disclosure relates to a droplet delivery device for delivery a fluid as an ejected stream of droplets to the pulmonary system of a subject and related methods of delivering safe, suitable, and repeatable dosages to the pulmonary system of a subject. The present disclosure also includes a droplet delivery device and system capable of delivering a defined volume of fluid in the form of an ejected stream of droplets such that an adequate and repeatable high percentage of the droplets are delivered into the desired location within the airways, e.g., the alveolar airways of the subject during use.
The present disclosure provides a droplet delivery device for delivery of a fluid as an ejected stream of droplets to the pulmonary system of a subject, the device comprising a housing, a reservoir for receiving a volume of fluid, and an ejector mechanism including a piezoelectric actuator and an aperture plate, wherein the ejector mechanism is configured to eject a stream of droplets having an average ejected droplet diameter of less than 5 microns. In specific embodiments, the ejector mechanism is activated by at least one differential pressure sensor located within the housing of the droplet delivery device upon sensing a pre-determined pressure change within the housing. In certain embodiments, such a pre-determined pressure change may be sensed during an inspiration cycle by a user of the device, as will be explained in further detail herein.
In accordance with certain aspects of the disclosure, effective deposition into the lungs generally requires droplets less than 5 μm in diameter. Without intending to be limited by theory, to deliver fluid to the lungs a droplet delivery device must impart a momentum that is sufficiently high to permit ejection out of the device, but sufficiently low to prevent deposition on the tongue or in the back of the throat. Droplets below 5 μm in diameter are transported almost completely by motion of the airstream and entrained air that carry them and not by their own momentum.
In certain aspects, the present disclosure includes and provides an ejector mechanism configured to eject a stream of droplets within the respirable range of less than 5 μm. The ejector mechanism is comprised of an aperture plate that is directly or indirectly coupled to a piezoelectric actuator. In certain implementations, the aperture plate may be coupled to an actuator plate that is coupled to the piezoelectric actuator. The aperture plate generally includes a plurality of openings formed through its thickness and the piezoelectric actuator directly or indirectly (e.g. via an actuator plate) oscillates the aperture plate, having fluid in contact with one surface of the aperture plate, at a frequency and voltage to generate a directed aerosol stream of droplets through the openings of the aperture plate into the lungs, as the patient inhales. In other implementations where the aperture plate is coupled to the actuator plate, the actuator plate is oscillated by the piezoelectric oscillator at a frequency and voltage to generate a directed aerosol stream or plume of aerosol droplets.
In certain aspects, the present disclosure relates to a droplet delivery device for delivering a fluid as an ejected stream of droplets to the pulmonary system of a subject. In certain aspects, the therapeutic agents may be delivered at a high dose concentration and efficacy, as compared to alternative dosing routes and standard inhalation technologies.
In certain embodiments, the droplet delivery devices of the disclosure may be used to treat various diseases, disorders and conditions by delivering therapeutic agents to the pulmonary system of a subject. In this regard, the droplet delivery devices may be used to deliver therapeutic agents both locally to the pulmonary system, and systemically to the body.
More specifically, the droplet delivery device may be used to deliver therapeutic agents as an ejected stream of droplets to the pulmonary system of a subject for the treatment or prevention of pulmonary diseases or disorders such as asthma, chronic obstructive pulmonary diseases (COPD) cystic fibrosis (CF), tuberculosis, chronic bronchitis, or pneumonia. In certain embodiments, the droplet delivery device may be used to deliver therapeutic agents such as COPD medications, asthma medications, or antibiotics. By way of non-limiting example, such therapeutic agents include albuterol sulfate, ipratropium bromide, tobramycin, and combinations thereof.
In other embodiments, the droplet delivery device may be used for the systemic delivery of therapeutic agents including small molecules, therapeutic peptides, proteins, antibodies, and other bioengineered molecules via the pulmonary system. By way of non-limiting example, the droplet delivery device may be used to systemically deliver therapeutic agents for the treatment or prevention of indications inducing, e.g., diabetes mellitus, rheumatoid arthritis, plaque psoriasis, Crohn's disease, hormone replacement, neutropenia, nausea, influenza, etc.
By way of non-limiting example, therapeutic peptides, proteins, antibodies, and other bioengineered molecules include: growth factors, insulin, vaccines (Prevnor—Pneumonia, Gardasil—HPV), antibodies (Avastin, Humira, Remicade, Herceptin), Fc Fusion Proteins (Enbrel, Orencia), hormones (Elonva—long acting FSH, Growth Hormone), enzymes (Pulmozyme—rHu-DNAase-), other proteins (Clotting factors, Interleukins, Albumin), gene therapy and RNAi, cell therapy (Provenge—Prostate cancer vaccine), antibody drug conjugates—Adcetris (Brentuximab vedotin for HL), cytokines, anti-infective agents, polynucleotides, oligonucleotides (e.g., gene vectors), or any combination thereof; or solid particles or suspensions such as Flonase (fluticasone propionate) or Advair (fluticasone propionate and salmeterol xinafoate).
In other embodiments, the droplet delivery device of the disclosure may be used to deliver a solution of nicotine including the water-nicotine azeotrope for the delivery of highly controlled dosages for smoking cessation or a condition requiring medical or veterinary treatment. In addition, the fluid may contain THC, CBD, or other chemicals contained in marijuana for the treatment of seizures and other conditions.
In certain embodiments, the drug delivery device of the disclosure may be used to deliver scheduled and controlled substances such as narcotics for the highly controlled dispense of pain medications where dosing is only enabled by doctor or pharmacy communication to the device, and where dosing may only be enabled in a specific location such as the patient's residence as verified by GPS location on the patient's smart phone. This mechanism of highly controlled dispensing of controlled medications can prevent the abuse or overdose of narcotics or other addictive drugs.
Certain benefits of the pulmonary route for delivery of drugs and other medications include a non-invasive, needle-free delivery system that is suitable for delivery of a wide range of substances from small molecules to very large proteins, reduced level of metabolizing enzymes compared to the GI tract and absorbed molecules do not undergo a first pass effect. (A. Tronde, et al., J Pharm Sci, 92 (2003) 1216-1233; A. L. Adjei, et al., Inhalation Delivery of Therapeutic Peptides and Proteins, M. Dekker, New York, 1997). Further, medications that are administered orally or intravenously are diluted through the body, while medications given directly into the lungs may provide concentrations at the target site (the lungs) that are about 100 times higher than the same intravenous dose. This is especially important for treatment of drug resistant bacteria, drug resistant tuberculosis, for example and to address drug resistant bacterial infections that are an increasing problem in the ICU.
Another benefit for giving medication directly into the lungs is that high, toxic levels of medications in the blood stream their associated side effects can be minimized. For example intravenous administration of tobramycin leads to very high serum levels that are toxic to the kidneys and therefore limits its use, while administration by inhalation significantly improves pulmonary function without severe side effects to kidney functions. (Ramsey et al., Intermittent administration of inhaled tobramycin in patients with cystic fibrosis. N Engl J Med 1999; 340:23-30; MacLusky et al., Long-term effects of inhaled tobramycin in patients with cystic fibrosis colonized with Pseudomonas aeruginosa. Pediatr Pulmonol 1989; 7:42-48; Geller et al., Pharmacokinetics and bioavailablility of aerosolized tobramycin in cystic fibrosis. Chest 2002; 122:219-226.)
As discussed above, effective delivery of droplets deep into the lung airways require droplets that are less than 5 microns in diameter, specifically droplets with mass mean aerodynamic diameters (MMAD) that are less than 5 microns. The mass mean aerodynamic diameter is defined as the diameter at which 50% of the particles by mass are larger and 50% are smaller. In certain aspects of the disclosure, in order to deposit in the alveolar airways, droplet particles in this size range must have momentum that is sufficiently high to permit ejection out of the device, but sufficiently low to overcome deposition onto the tongue (soft palate) or pharynx.
In other aspects of the disclosure, methods for generating an ejected stream of droplets for delivery to the pulmonary system of user using the droplet delivery devices of the disclosure are provided. In certain embodiments, the ejected stream of droplets is generated in a controllable and defined droplet size range. By way of example, the droplet size range includes at least about 50%, at least about 60%, at least about 70%, at least about 85%, at least about 90%, between about 50% and about 90%, between about 60% and about 90%, between about 70% and about 90%, etc., of the ejected droplets are in the respirable range of below about 5 μm.
In other embodiments, the ejected stream of droplets may have one or more diameters, such that droplets having multiple diameters are generated so as to target multiple regions in the airways (mouth, tongue, throat, upper airways, lower airways, deep lung, etc.) By way of example, droplet diameters may range from about 1 μm to about 200 μm, about 2 μm to about 100 μm, about 2 μm to about 60 μm, about 2 μm to about 40 μm, about 2 μm to about 20 μm, about 1 μm to about 5 μm, about 1 μm to about 4.7 μm, about 1 μm to about 4 μm, about 10 μm to about 40 μm, about 10 μm to about 20 μm, about 5 μm to about 10 μm, and combinations thereof. In particular embodiments, at least a fraction of the droplets have diameters in the respirable range, while other particles may have diameters in other sizes so as to target non-respirable locations (e.g., larger than 5 μm). Illustrative ejected droplet streams in this regard might have 50%-70% of droplets in the respirable range (less than about 5 μm), and 30%-50% outside of the respirable range (about 5 μm-about 10 μm, about 5 μm-about 20 μm, etc.)
In another embodiment, methods for delivering safe, suitable, and repeatable dosages of a medicament to the pulmonary system using the droplet delivery devices of the disclosure are provided. The methods deliver an ejected stream of droplets to the desired location within the pulmonary system of the subject, including the deep lungs and alveolar airways.
In certain aspects of the disclosure, a droplet delivery device for delivery an ejected stream of droplets to the pulmonary system of a subject is provided. The droplet delivery device generally includes a housing and a reservoir disposed in or in fluid communication with the housing, an ejector mechanism in fluid communication with the reservoir, and at least one differential pressure sensor positioned within the housing. The differential pressure sensor is configured to activate the ejector mechanism upon sensing a pre-determined pressure change within the housing, and the ejector mechanism is configured to generate a controllable plume of an ejected stream of droplets. The ejected stream of droplets includes, without limitation, solutions, suspensions or emulsions which have viscosities in a range capable of droplet formation using the ejector mechanism. The ejector mechanism may include a piezoelectric actuator which is directly or indirectly coupled to an aperture plate having a plurality of openings formed through its thickness. The piezoelectric actuator is operable to directly or indirectly oscillate the aperture plate at a frequency to thereby generate an ejected stream of droplets.
In certain embodiments, the droplet delivery device may include a combination reservoir/ejector mechanism module that may be replaceable or disposable either on a periodic basis, e.g., a daily, weekly, monthly, as-needed, etc. basis, as may be suitable for a prescription or over-the-counter medication. The reservoir may be prefilled and stored in a pharmacy for dispensing to patients or filled at the pharmacy or elsewhere by using a suitable injection means such as a hollow injection syringe driven manually or driven by a micro-pump. The syringe may fill the reservoir by pumping fluid into or out of a rigid container or other collapsible or non-collapsible reservoir. In certain aspects, such disposable/replaceable, combination reservoir/ejector mechanism module may minimize and prevent buildup of surface deposits or surface microbial contamination on the aperture plate, owing to its short in-use time.
The present disclosure also provides a droplet delivery device that is altitude insensitive. In certain implementations, the droplet delivery device is configured so as to be insensitive to pressure differentials that may occur when the user travels from sea level to sub-sea levels and at high altitudes, e.g., while traveling in an airplane where pressure differentials may be as great as 4 psi. As will be discussed in further detail herein, in certain implementations of the disclosure, the droplet delivery device may include a superhydrophobic filter which provides for free exchange of air across the filter into and out of the reservoir, while blocking moisture or fluids from passing through the filter, thereby reducing or preventing fluid leakage or deposition on aperture plate surfaces.
Reference will now be made to the figures, with like components illustrates with like references numbers.
Referring to
By way of non-limiting example,
Once activated, the droplet delivery device of the disclosure may be actuated to delivery an ejected stream of droplets for any suitable time sufficient to deliver the desired dosage. For instance, the piezoelectric actuator may be activated to the oscillate the aperture plate to thereby generate the ejected stream of droplets for a short burst of time, e.g., one tenth of a second, or for sever seconds, e.g., 5 second. In certain embodiments, the droplet delivery device may be activated to generate and deliver the ejected stream of droplets, e.g., for up to about 5 seconds, up to about 4 seconds, up to about 3 seconds, up to about 2 seconds, up to about 1 second, between about 1 second and about 2 seconds, between about 0.5 seconds and 2 seconds, etc.
In certain embodiments, any suitable differential pressure sensor with adequate sensitivity to measure pressure changes obtained during standard inhalation cycles may be used, e.g., ±5 SLM, 10 SLM, 20 SLM, etc. For instance, pressure sensors from Sensirion, Inc., SDP31 or SDP32 (U.S. Pat. No. 7,490,511 B2) are particularly well suited for these applications.
In certain embodiments of the present disclosure, the signal generated by the pressure sensors provides a trigger for activation and actuation of the ejector mechanism of the droplet delivery device at or during a peak period of a patient's inhalation (inspiratory) cycle and assures optimum deposition of the ejected stream of droplets and delivery of the medication into the pulmonary airways of the user.
In addition, an image capture device, including cameras, scanners, or other sensors without limitation, e.g. charge coupled device (CCD), may be provided to detect and measure the ejected aerosol plume. These detectors, LED, delta P transducer, CCD device, all provide controlling signals to a microprocessor or controller in the device used for monitoring, sensing, measuring and controlling the ejection of fluid and reporting patient compliance, treatment times, dosage, and patient usage history, etc., via Bluetooth, for example.
In certain aspects of the disclosure, the ejector mechanism, reservoir, and housing/mouthpiece function to generate a plume or aerosol of fluid with droplet diameters less than 5 um. As discussed above, in certain embodiments, the reservoir and ejector mechanism are integrated to form a combination reservoir/ejector mechanism module which comprises the piezoelectric actuator powered by electronics in the device housing and a drug reservoir which may carry sufficient fluid for just a few or several hundred doses of medicament.
In certain embodiments, as illustrated herein, the combination module may have a pressure equalization port or filter to minimize leakage during atmospheric pressure changes such as on a commercial airliner. The combination module may also include components that may carry information read by the housing electronics including key parameters such as actuator frequency and duration, drug identification, and information pertaining to patient dosing intervals. Some information may be added to the module at the factory, and some may be added at the pharmacy. In certain embodiments, information placed by the factory may be protected from modification by the pharmacy. The module information may be carried as a printed barcode or physical barcode encoded into the module geometry (such as light transmitting holes on a flange which are read by sensors on the housing). Information may also be carried by a programmable or non-programmable microchip on the module which communicates to the electronics in the housing via the piezoelectric power connection. For example, each time the device is turned on, the cartridge may be sent minimal voltage, e.g., five volts through the piezoelectric power connection which causes the data chip to send a low-level pulse stream back to the electronics via the same power connection.
By way of example, module programming at the factory or pharmacy may include a drug code which may be read by the device, communicated via Bluetooth to an associated user smartphone and then verified as correct for the user. In the event a user inserts an incorrect, generic, damaged, etc., module into the device, the smartphone might be prompted to lock out operation of the device, thus providing a measure of user safety and security not possible with passive inhaler devices. In other embodiments, the device electronics can restrict use to a limited time period (perhaps a day, or weeks or months) to avoid issues related to drug aging or the gradual buildup of contamination on the aperture plate.
An airflow sensor located in the device aerosol delivery tube measures the inspiratory and expiratory flow rates flowing in and out of the mouthpiece. This sensor is placed so that it does not interfere with drug delivery or become a site for collection of residue or promote bacterial growth or contamination. A differential (or gage) pressure sensor downstream of a flow restrictor (e.g., laminar flow element) measures airflow based upon the pressure differential between the inside of the mouthpiece relative to the outside air pressure. During inhalation (inspiratory flow) the mouthpiece pressure will be lower than the ambient pressure and during exhalation (expiratory flow) the mouthpiece pressure will be greater than the ambient pressure. The magnitude of the pressure differential during an inspiratory cycle is a measure of the magnitude of airflow and airway resistance at the air inlet end of the aerosol delivery tube.
In one embodiment, referring to
The components may be packaged in a housing 116, which may be disposable or reusable. The housing 116 may be handheld and may be adapted for communication with other devices via a Bluetooth communication module 118 or similar wireless communication module, e.g., for communication with a subject's smart phone, tablet or smart device (not shown). In one embodiment, laminar flow element 120 may be located at the air entry side of the housing 116 to facilitate laminar airflow across the exit side of aperture plate 108 and to provide sufficient airflow to ensure that the ejected stream of droplets flow through the device during use. Aspects of the present embodiment further allows customizing the internal pressure resistance of the droplet delivery device by allowing the placement of laminar flow elements having openings of different sizes and varying configurations to selectively increase or decrease internal pressure resistance, as will be explained in further detail herein.
Droplet delivery device 100 may further include various sensors and detectors 122, 124, 126, and 128 to facilitate device activation, spray verification, patient compliance, diagnostic mechanisms, or as part of a larger network for data storage, big data analytics and for interacting and interconnected devices used for subject care and treatment, as described further herein. Further, housing 116 may include an LED assembly 130 on a surface thereof to indicate various status notifications, e.g., ON/READY, ERROR, etc.
Referring more specifically to
The airflow exit of housing 116 of the droplet delivery device 100 of
In another embodiment (not shown), a mini fan or centrifugal blower may be located at the air inlet side of the laminar flow element 120 or internally of the housing 116 within the airsteam. The mini fan generally may provide additional airflow and pressure to the output of the airstream. For patients with low pulmonary output, this additional airstream may ensure that the ejected stream of droplets is pushed through the device into the patient's airway. In certain implementations, this additional source of airflow ensures that the ejector face is swept clean of the ejected droplets and also provides mechanism for spreading the droplet plume into an airflow which creates greater separation between droplets. The airflow provided by the mini fan may also act as a carrier gas, ensuring adequate dose dilution and delivery.
With reference to
A series of colored lights powered by an LED assembly are located in the front region of the ejector device. In this embodiment, the LED assembly 130, including, e.g., four LED's, 130A, and an electronics board 130B, on which the LED assembly 130 is mounted and provides an electrical connection to the main electronics board 102. The LED assembly 130 may provide the user with immediate feedback on functions such as, power, ON and OFF, to signal when breath activation occurs (as described further herein), to provide the user with feedback as to when an effective or ineffective dispense of a dose is delivered (as described further herein), or to provide other user feedback to maximize patient compliance.
The laminar flow element 120 is located opposite the patient use end of the mouthpiece tube 154, and a differential pressure sensor 122, pressure sensor electronics board 160, and pressure sensor O-ring 162 are located nearby.
The remaining components detailed in
Again, with reference to
The aerosol delivery mouthpiece tube may be removable, replaceable and sterilizable. This feature improves sanitation for drug delivery by providing means and ways to minimize buildup of aerosolized medication within the mouthpiece tube by providing ease of replacement, disinfection and washing. In one embodiment, the mouthpiece tube may be formed using sterilizable and transparent polymer compositions such as polycarbonate, polyethylene or polypropylene, and not limited by example. With reference to
In other embodiments, the internal pressure resistance of the droplet delivery device may be customized to an individual user or user group by modifying the mouthpiece tube design to include various configurations of air aperture grids or openings, thereby increasing or decreasing resistance to airflow through the device as the user inhales. For instance, with reference to
Referring to
Any suitable material may be used to form the housing of the droplet delivery device. In particular embodiment, the material should be selected such that it does not interact with the components of the device or the fluid to be ejected (e.g., drug or medicament components). For example, polymeric materials suitable for use in pharmaceutical applications may be used including, e.g., gamma radiation compatible polymer materials such as polystyrene, polysulfone, polyurethane, phenolics, polycarbonate, polyimides, aromatic polyesters (PET, PETG), etc.
In certain aspects of the disclosure, an electrostatic coating may be applied to the one or more portions of the housing, e.g., inner surfaces of the housing along the airflow pathway, to aid in reducing deposition of ejected droplets during use due to electrostatic charge build-up. Alternatively, one or more portions of the housing may be formed from a charge-dissipative polymer. For instance, conductive fillers are commercially available and may be compounded into the more common polymers used in medical applications, for example, PEEK, polycarbonate, polyolefins (polypropylene or polyethylene), or styrenes such as polystyrene or acrylic-butadiene-styrene (ABS) copolymers.
As mentioned above, in certain configurations of the disclosure, the reservoir and ejector mechanism may be integrated together into a combination reservoir/ejector mechanism module that may be removable and/or disposable. In certain embodiments, the combination reservoir/ejector mechanism module may be vertically orientated such that the surface tension plate may facilitate fluid contact between the fluid in the reservoir and the fluid contact surface of the aperture plate. In other configurations, the combination reservoir/ejector mechanism module be horizontally oriented within the device and positioned such that the fluid within the reservoir is in constant contact with the fluid contact surface of the aperture plate.
For instance, with reference to
In certain embodiments, module 400 may further include a seal 404C, which seals the fill hole used to dispense fluid into the ampule. Other components include a polymer cap 406 which seals the top of the ampule, a housing cup 408 which includes the surface tension plate 114, an O-ring structure 410 which supports the aperture plate 108 and piezoelectric actuator 106, which make electrical contact to the electronics through connector pins 412.
Also included in the module 400 is an optional bar code (not shown) which may provide electrical contact and electrical feed to the piezoelectric actuator 106, as well as provide information on the drug type, initial drug volume, concentration, e.g.; dosing information such as single or multiple dosing regimens, dosing frequency and dosing times. Additional information that may be included on the barcode which may identify the type of aperture plate, target droplet size distribution and target site of action in the pulmonary airways or body, in general. Alternatively, this information may be carried on an electronic chip embedded in the module which can be read either via a wireless connection or via a signal carried by the piezoelectric power connection or via one or more additional physical contacts. Other information included on the barcode or chip may provide critical drug content information or cartridge identification which may prevent improper use of the device or accidental insertion of expired or improper medication, for example.
In certain embodiments, the droplet delivery devices of the disclosure may further include an ejector closure mechanism, which may provide a closure barrier to restrict evaporation of reservoir fluid through the aperture plate and may provide a protective barrier from contamination for the aperture plate and reservoir. As will be understood by those of skill in the art, together with the reservoir, the ejector closure mechanism may provide for a protective enclosure of the reservoir/ejector mechanism module to thereby minimize evaporative loss, contamination, and/or intrusion of foreign substances into the reservoir during storage.
With reference to
With reference to
As described herein, the droplet delivery device of the disclosure generally may include a laminar flow element located at the air entry side of the housing. The laminar flow element, in part, facilitates laminar airflow across the exit side of aperture plate and provides sufficient airflow to ensure that the ejected stream of droplets flows through the droplet delivery device during use. The laminar flow element allows for customization of internal device pressure resistance by designing openings of different sizes and varying configurations to selectively increase or decrease internal pressure resistance.
In certain embodiments, the laminar flow element is designed and configured in order to provide an optimum airway resistance for achieving peak inspirational flows that are required for deep inhalation which promotes delivery of ejected droplets deep into the pulmonary airways. Laminar flow elements also function to promote laminar flow across the aperture plate, which also serves to stabilize airflow repeatability, stability and insures an optimal precision in the delivered dose.
Without intending to be limited by theory, in accordance with aspects of the disclosure, the size, number, shape and orientation of holes in the laminar flow element of the disclosure may be configured to provide a desired pressure drop within the droplet delivery device. In certain embodiments, it may be generally desirable to provide a pressure drop that is not so large as to strongly affect a user's breathing or perception of breathing.
In this regard,
Referring to
Referring to
In certain implementations, the use of laminar flow elements having different sized holes, or the use of adjustable apertures may be required in order to accommodate the differences among the lungs and associated inspiratory flow rates of young and old, small and large, and various pulmonary disease states. For example, if the aperture is adjustable by the patient (perhaps by having a slotted ring that can be rotated), then a method may be provided to read the aperture hole setting and lock that position to avoid inadvertent changes of the aperture hole size, hence the flow measurement. Although pressure sensing is an accurate method for flow measurement, other embodiments may use, e.g., hot wires or thermistor types of flow rate measurement methods which lose heat at a rate proportional to flow rate, moving blades (turbine flow meter technology) or by using a spring-loaded plate, without limitation of example.
As described herein, the droplet delivery device of the disclosure generally may include an ejector mechanism including a piezoelectric actuator coupled directly or indirectly to an aperture plate, the aperture plate having a plurality of openings formed through its thickness. The plurality of openings may have a variety of shapes, sizes and orientations. With reference to
The aperture plate may have any suitable size, shape or material. For example, the aperture plate may have a circular, annular, oval, square, rectangular, or a generally polygonal shape. Further, is accordance with aspects of the disclosure, the aperture plate may be generally planar or may have a concave or convex shape. In certain embodiments, the aperture plate may have a generally domed or half-spherical shape. By way of non-limiting example, with reference to
In this regard, in certain aspects of the disclosure, it was unexpectedly found that improved ejector mechanism performance may be obtained with aperture plates having a generally domed-shape. Referring to
Referring to
In certain implementations of the disclosure, design parameters that define the domed shape geometry of an exemplary aperture plate include dome height, active area (region including the plurality of openings), and shape and geometry of the dome. Referring to
As indicated in the table below, performance comparisons of aperture plates with planar versus domed shapes with regard to droplet generation efficiency as measured by ml of fluid ejected per minute shows that the domed shape provides a significant improvement in performance.
These data indicate that the planar surface ejects 0.5 mL/min over an active surface area of 28.3 mm2 footprint (area) and the domed surface ejects 0.7 mL/min from just a 3.1 mm2 active surface area footprint for similar openings. In other words, the domed surface ejects 12.6 times more mass per unit area of active surface area footprint as compared to the planar surface.
The aperture plate of the disclosure may be formed from any suitable material known in the art for such purposes. By way of non-limiting example, the aperture plate may be composed of a pure metal, metal alloy or high modulus polymeric material, such as, and not limited by example, Ni, NiCo, Pd, Pt, NiPd, or other metals or alloy combinations, polyether ether ketone (PEEK), polyimide (Kapton), polyetherimide (Ultem), polyvinylidine fluoride (PVDF), ultra-high molecular weight polyethylene (UHMWPE), as well as a range of filler materials blended into polymers to enhance physical and chemical properties may be used for aperture plate designs and fabrication. Filler materials can include but are not limited to glass and carbon nanotubes. These materials may be used to increase the yield strength and the stiffness or modulus of elasticity. In one embodiment, the aperture plate may be obtained from Optnics Precision Co. LTD. model No. TD-15-05B-OPT-P90-MED.
In certain embodiments, it may be desirable to provide coatings or surface modification to the aperture plates (chemical or structural) in order to enhance microfluidic properties, render surfaces either hydrophilic or hydrophobic or render surfaces antimicrobial.
In certain implementations of the disclosure an aperture plate formed from the high modulus polymeric may be processed to reduce residual stresses that may accumulate in its morphology and thickness during film formation and fabrication. For example, annealing of PEEK film is a standard procedure suggested by Victrex to obtain optimized crystallinity and to allow relaxation of intrinsic stresses. (www.victrex.com). The systems and methods for releasing residual stresses in high modulus polymeric materials may provide increased yield strength of an aperture plate formed from such materials so as to optimize its stability in the oscillations of the aperture plate as well as minimize plastic deformation of the entrance and exit orifice geometries of the nozzle plate during actuation. In this regard, the systems and methods for releasing residual stresses in the high modulus polymeric aperture plate may insure delivery and administration of a repeatable, consistent dose of medicament.
Further, PEEK, due to its desirable mechanical performance in dynamic loading and its resistance up to high temperatures, is easily laser micromachined and excimer laser ablated, making it a suitable material for fabrication of aperture plates. By way of a non-limiting example, laser excimer treatment of polymer surfaces, and PEEK surfaces in particular, may be used for surface treatment of PEEK aperture plates in order to improve adhesive bonding of the piezoelectric ceramic to the PEEK aperture plate. (P. Laurens, et al., Int. J. Adhes. (1998) 18). In addition, laser ablation and fine machining of PEEK may be used to form parallel grooves or other surface structures, which may lead to the formation of superhydrophobic regions on selected surface areas of the PEEK aperture plates, which may inhibit the drug solution or suspension from wetting selected regions of the aperture plate.
By way of non-limiting example, the plurality of openings may range in average diameter from about 1 μm to about 200 μm, about 2 μm to about 100 μm, about 2 μm to about 60 μm, about 2 μm to about 40 μm, about 2 μm to about 20 μm, about 2 μm to about 5 μm, about 1 μm to about 2 μm, about 2 μm to about 4 μm, about 10 μm to about 40 μm, about 10 μm to about 20 μm, about 5 μm to about 10 μm, etc. Further, in certain embodiments, various openings on an aperture plate may have the same or different sizes or diameters, e.g., some may have an average diameter in a range of about 1 μm to about 2 μm and others may have a diameter of about 2 μm to about 4 μm or about 5 μm to about 10 μm, etc. For instance, holes of differing sizes may be used to generate droplets within a varied size range to target different areas of the pulmonary system, e.g., to target the tongue, oral cavity, pharynx, trachea, upper airways, lower airways, deep lunges, and combinations thereof.
Aperture plate thickness may range from about 10 μm to about 300 μm, about 10 μm to about 200 μm, about 10 to about 100 μm, about 25 μm to about 300 μm, about 25 μm to about 200 μm, about 25 μm to about 100 μm, etc. Further, the number of openings in the aperture plate may range from, e.g., about 5 to about 5000, about 50 to about 5000, about 100 to about 5000, about 250 to about 4000, about 500 to about 4000, etc. It certain embodiments, the number of openings may be increased or decreased by increasing or decreasing the aperture plate pitch (i.e., opening center-to-center distance). In this regard, an increase in the packing density, i.e. reducing the pitch distance, and increasing the number of opening in the aperture plate leads to an increase in the total droplet ejected volume.
In certain implementations, the openings in the aperture plate may have a generally cylindrical shape, tapered, conical, or hour-glass shape. In certain embodiments, the openings may have a generally fluted shape, with a larger opening at one surface of the aperture plate, a smaller opening at the opposite surface of the aperture plate, and a capillary therebetween. The larger and smaller of the openings may be oriented towards the fluid entrance or fluid exit surface of the aperture plate, as desired.
In the embodiment shown in
Referring to
Ec=t−CL
where the fluid entrance side opening diameter (Den) is equal to 2× the entrance cavity radius of curvature, plus the fluid exit side opening diameter (Dex):
Den=2(Ec)+Dex
In certain embodiments, optimization of the aspect ratio of the fluid entrance to the fluid exit diameters, in combination with capillary lengths, allows for formation of ejected droplets of fluids having relatively high viscosities.
Any suitable method may be used to manufacture the aperture plates and the plurality of openings within the apertures plates, as may be known in the art and as may suitable for the particular material of interest. By way of example, micromaching, pressing, laser ablation, LIGA, thermoforming, etc. may be used. In particular, laser ablation of polymers is an established process for industrial applications. Excimer laser micromachining is particularly well suited for fabrication of polymeric aperture plates. However, the disclosure is not so limited and any suitable method may be used.
As described herein, the ejector mechanism of the disclosure also comprises a piezoelectric actuator. Piezoelectric actuators are well known in the art as electronic components used as sensors, droplet ejectors or micro pumps, for example. When a voltage is applied across a piezoelectric material, the crystalline structure of the piezoelectric is affected such that the piezoelectric material will change shape. When an alternating electric field is applied to a piezoelectric material, it will vibrate (contracting and expanding) at the frequency of the applied signal. This property of piezoelectric materials can be exploited to produce effective actuators, to displace a mechanical load. As voltage is applied to a piezoelectric actuator, the resulting change in the piezoelectric material's shape and size displaces the load.
As described herein, in certain aspects, the piezoelectric actuator drives the oscillation of the aperture plate which produces the vibration that leads to the formation of the ejected stream of droplets. As an alternating voltage is applied to electrodes on the surface of the piezoelectric actuator, the aperture plate oscillates and a stream of droplets are generated and ejected from the openings in the aperture plate along a direction away from the fluid reservoir.
The piezoelectric actuator may be formed from any suitable piezoelectric material or combination of materials. By way of non-limiting example, suitable piezoelectric materials include ceramics that exhibit the piezoelectric effect such as lead zirconate titanate (PZT), lead-titanate (PbTiO2), lead-zirconate (PbZrO3), or barium titanate (BaTiO3). Further, the piezoelectric actuator may have any suitable size and shape, so as to be compatible to oscillate the aperture plate. By way of example, the piezoelectric actuator may have a generally annulus or ring shape, with a center opening that accommodates the active area (the region with the plurality of openings) of the aperture plate so as to allow the ejected stream of droplets to pass through the aperture plate.
In this regard, the use of axisymmetric piezoelectric actuators in the form of an annulus or ring to produce motion in a generally circular substrate plate for a variety of microfluidic applications is well known. A range of actuating voltages may be used as a periodic voltage signal applied in a variety of waveforms, e.g., sinusoidal, square or other implementations, and the direction of the voltage differential may be periodically reversed with the period of oscillation dependent on the resonant frequency of the piezoelectric material, for example to +15V to −15V, or a range peak-to-peak from 5V to 250V. In embodiments of the disclosure, any suitable voltage signal and waveform may be applied to obtain the desired vibration and actuation of the aperture plate.
In piezoelectric actuated devices, the frequency and amplitude of the signal driving the piezoelectric actuator has a significant effect on the behavior of the piezoelectric actuator and its displacement. It is also well known that when the piezoelectric element is at resonance, the piezoelectric device will achieve the greatest displacement of its mechanical load as well as achieve its highest operating efficiency. In addition, a variety of factors can impact the magnitude of displacement of the aperture plate. Factors such as the drive signal of the piezoelectric actuator, the selected resonant frequency, and Eigen mode. Other factors include be include losses due to the piezoelectric material which originate from its dielectric response to an electrical field and its mechanical response to applied stress, or conversely, the charge or voltage generation as a response to the applied stress.
In addition, the electrical and mechanical response of the piezoelectric actuator is also a function of fabrication methodology, the configuration and dimensions of the piezoelectric actuator, the position and placement of the mechanical mounting of the piezoelectric actuator onto the aperture plate and droplet delivery device, and the piezoelectric electrode size and mounting, for example.
In another aspect of the disclosure, the reservoir may be configured to include an internal flexible drug ampoule to provide an airtight drug container. With reference to
In accordance with embodiments of the disclosure, the flexible drug ampule may be formed using conventional form-fill-seal processes. Medical film materials that are available for its structure are shown below and include primarily micro-thick (e.g., 2-4 mil), low density polyethylene film.
In another aspect of the disclosure, the droplet delivery device may comprise a surface tension plate placed in proximity to the aperture plate on the fluid contact side of the aperture plate. As described above, the surface tension plate, at least in part, directs and focuses fluid to the aperture plate. More particularly, in certain embodiments, the surface tension plate may be on the on the fluid contact side of the aperture plate so as to provide for a uniform distribution of fluid onto the aperture plate from the reservoir. In certain aspects of the disclosure, as will be described in further detail herein, the distance of placement of the surface tension plate from the aperture plate provides for an optimization of performance of the ejector mechanism, as measured by ejected droplet mass rate.
Without intending to be limited, the surface tension plate may have a grid of perforations or holes of various sizes and configurations that may have circular, square, hexagonal, triangular or other cross-sectional shapes. In certain embodiments, the perforations or holes may be located along the perimeter, the center, or throughout the entirety of the surface tension plate. Any suitable size and configuration of perforations or holes may be used such that the desired hydrostatic pressure and capillary action is achieved, as described herein.
In certain embodiments, as illustrated in
Without intending to be limited by theory, the surface tension plate generates hydrostatic pressure behind the aperture plate, whose magnitude is dependent on the spacing between the surface tension plate and the aperture plate. For example, hydrostatic pressure exerted by fluid increases as the spacing between the surface tension plate and the aperture plate decreases. Furthermore, as the surface tension plate distance from the aperture plate decreases, there is an increase in hydrostatic pressure that is manifested as capillary rise in fluid between the surface tension plate and aperture plate. In this manner, the placement of a surface tension plate on the fluid contact side of the aperture plate can help provide for a constant supply of fluid to the active area of the aperture plate, regardless of the orientation of the inhaler device.
Referring to
As illustrated in
While the droplet delivery devices of the disclosure are not so limited, based on surface energy differences between materials of construction, as well as the inverse relationship between hydrostatic forces and distance between the surface tension plate and the aperture plate; surface tension plate distances greater than about 2 mm may not provide sufficient capillary action or hydrostatic force to ensure a constant supply of fluid to the aperture plate. As such, in certain embodiments, the surface tension plate may be placed within about 2 mm of the aperture plate, within about 1.9 mm of the aperture plate, within about 1.8 mm of the aperture plate, within about 1.7 mm of the aperture plate, within about 1.6 mm of the aperture plate, within about 1.5 mm of the aperture plate, within about 1.4 mm of the aperture plate, within about 1.3 mm of the aperture plate, within about 1.2 mm of the aperture plate, within about 1.1 mm of the aperture plate, within about 1 mm of the aperture plate, etc.
In another embodiment of the disclosure, the droplet delivery device may include two or more, three or more, four or more reservoirs, e.g., a multiple or dual reservoir configuration. In certain embodiments, the multiple or dual reservoir may be a combination multiple or dual reservoir/ejector module configuration, which may be removable and/or disposable. The multiple or dual reservoir can deliver multiple medications, flavors, or a combination thereof for polypharmacy.
In certain aspects, this system and methods provides a multiple or dual reservoir configuration that can deliver multiple medications prescribed to a patient, and which may be delivered through the same device. This may be particularly useful for subjects that take medications for multiple indications, or that require multiple medications for the same indication. In accordance with the disclosure, the droplet delivery device may be programmed to administer the proper medication in the proper dosage according to the proper administration schedule, e.g., based on barcode or embedded chip information programmed at the pharmacy.
By way of non-limiting example,
More specifically, the combination dual reservoir/ejector mechanism module may have aperture plates that are similar in design and able to generate ejected droplets with similar droplet size distributions that are targeted for similar regions of the pulmonary airways. Alternatively, use of multiple medications or polypharmacy, may require delivery of medications to different areas of the pulmonary airways. Under these circumstances, each reservoir of the dual reservoir/ejector mechanism module may have an aperture plate with different opening configurations (e.g., different entrance and/or exit opening sizes, spacings, etc.) to deliver different droplet size distributions targeting different regions of the pulmonary airways.
In other embodiments, the disclosure also provides a single or dual disposable/reusable drug reservoir/ejector module that can deliver multiple medications, flavors, or combinations thereof for polypharmacy in which the aperture plate may include openings with multiple size configurations (e.g., different entrance and/or exit opening sizes, spacings, etc.). Aperture plates with openings having multiple size configurations generate droplets of different size distributions, thereby targeting different regions of the pulmonary airways. Although many-sized-hole combinations are possible, by way of non-limiting example, various combinations and densities of openings having average exit diameters of e.g., about 1 μm, about 1 μm, about 3 μm, about 4 μm, about 10 μm, about 15 μm, about 20 μm, about 30 μm, about 40 μm, etc.
By way of non-limiting example, one opening may have an average exit diameter of 4 μm and an octagonal array of 8 larger openings having an average exit diameter of 20 μm. In this manner, the aperture plate may deliver both larger droplets (about 20 μm in diameter) as well as smaller droplets (about 4 μm in diameter), which can target different regions of the pulmonary airways and which, for example, may simultaneously deliver flavors to the throat and medication to the deep alveolar passageways.
Another aspect of the present disclosure as described herein, provides droplet delivery device configurations and methods to increase the respirable dose of an ejected stream of droplets by filtering and excluding larger droplets (having a MMAD larger than about 5 μm) from the aerosol plume by virtue of their higher inertial force and momentum (referred to herein as “inertial filtering”). In the event that droplet particles having MMAD larger than 5 μm are generated, their increased inertial mass may provide a means of excluding these larger particles from the airstream by deposition onto the mouthpiece of the droplet delivery device. This inertial filter effect of the drug delivery device of the disclosure further increases the respirable dose provided by the device, thus providing improved targeting delivery of medication to desired regions of the airways during use.
Without intending to be limited by theory, aerosol droplets have an initial momentum that is large enough to be carried by the droplet plume emerging from the aperture plate. When a gas stream changes direction as it flows around an object in its path, suspended particles tend to keep moving in their original direction due to their inertia. However, droplets having MMAD larger than 5 μm generally have a momentum that is sufficiently large to deposit onto the sidewall of the mouthpiece tube (due to their inertial mass), instead of being deflected and carried into the airflow.
Inertial mass is a measure of an object's resistance to acceleration when a force is applied. It is determined by applying a force to an object and measuring the acceleration that results from that force. An object with small inertial mass will accelerate more than an object with large inertial mass when acted upon by the same force.
To determine the inertial mass of a droplet particle, a force of F, Newtons is applied to an object, and the acceleration in m/s2 is measured. Inertial mass, m, is force per acceleration, in kilograms. Inertial force, as the name implies is the force due to the momentum of the droplets. This is usually expressed in the momentum equation by the term (ρv)v. So, the denser a fluid, and the higher its velocity, the more momentum (inertia) it has.
The first derivation of the momentum with time is Force
I—Moment of inertia
With reference to
In certain embodiments, larger droplets may be allowed to pass through the droplet delivery device within the effects of inertial filtering or with varied effects of inertial filtering. For instance, the incoming airstream velocity may be increased (e.g., through use of the mini-fan described herein) so larger droplet particles may be carried into the pulmonary airways. Alternatively, the exit angle of the mouthpiece tube may be varied (increased or decreased) to allow for deposition of droplets of varying sizes on the sidewalls of the mouthpiece. By way of example, with reference to
In another aspect of the disclosure, in certain embodiments, the droplet delivery devices provide for various automation, monitoring and diagnostic functions. By way of example, as described above, device actuation may be provided by way of automatic subject breath actuation. Further, in certain embodiments, the device may provide automatic spray verification, to ensure that the device has generated the proper droplet generation and provided to proper dosing to the subject. In this regard, the droplet delivery device may be provided with one or more sensors to facilitate such functionality.
More specifically, in certain embodiments, the droplet delivery device may provide automatic spray verification via LED and photodetector mechanisms. With reference to
By way of example, the concentration of a medicament in the ejected fluid may be made, according to Beer's Law Equation (Absorbance=e L c), where, e is the molar absorptivity coefficient (or molar extinction coefficient) which is a constant that is associated with a specific compound or formulation, L is the path length or distance between LED emitter and photodetector, and c is the concentration of the solution. This implementation provides a measure of drug concentration and can be used for verification and a means and way to monitoring patient compliance as well as to detect the successful delivery of medication.
Referring to
In yet other embodiments, spray verification and dose verification may be achieved by formulating the fluid/drug to include a compound that fluoresces (or the fluid/drug may naturally fluoresce). Upon delivery of the stream of droplets, the fluorescence may be measured using standard optical means. The light source used for measurement may be modulated, to minimize the effects of external light. When mounted, so that the light path is parallel to and directly across the aperture plate, the generation of droplets by the aperture plate may be directly measured. This direct measurement can allow direct confirmation that the aperture plate is primed and working correctly. When mounted between the droplet exit and the aperture plate, the aerosol plume may be monitored as it passes through the droplet delivery device. The optical means may be any conventional LED with a relatively narrow beam and a half-angle less than twenty degrees. Alternatively, a laser diode may be used to produce a very narrow, collimated beam that will reflect off individual droplets. Various wavelengths from the near UV to the near IR have been used to successfully measure aerosol plume absorption in transmission mode. By using very short wavelength LEDs that are less than 280 nm, interference from sunlight or other conventional light sources can be avoided by placing a filter on the detector than attenuates wavelengths longer than 275 nm. Similarly, if a fluorescing material is added to the fluid/drug, an optical bandpass filter may be placed in front of the detector in order to avoid interference from the stimulation light or external light. Restriction of the ambient light may also be accomplished by utilizing vanes or shades as part of the air-restriction aperture between the device and ambient air.
In another aspect of the disclosure, the droplet delivery device may be used in connection with or integrated with breathing assist devices such as a mechanical ventilator or portable Continuous Positive Airway Pressure (CPAP) machine, to provide in-line dosing of therapeutic agents with the breathing assistance airflow.
For example, mechanical ventilators with endo-tracheal (ET) tubes are used to block secretions from entering the lungs of an unconscious patient and/or to breathe for the patient. The ET tube seals to the inside of the trachea just below the larynx with an inflatable balloon. However, common undesirable side-effects that result from use of mechanical ventilators include ventilator-assisted pneumonia (VAP), which occurs in about ⅓ of patients who are on ventilators for 48 hours or more. As a result, VAP is associated with high morbidity (20% to 30%) and increased health care systems costs. (Fernando, et al., Nebulized antibiotics for ventilation-associated pneumonia: a systematic review and meta-analysis. Critical Care 19:150 2015).
Tobramycin administration through the pulmonary route is generally regarded as superior to intravenous administration for treating VAP, with nebulizers being typically used to deliver the antibiotics through generation of a continuous stream of droplets into the ventilator airflow. The main benefit of inhaled versus oral or intravenous administered antibiotics is the ability to deliver a higher concentration of the antibiotic directly into the lungs. However, continuous generation of nebulizer mist provides imprecise dosing that cannot be verified between inhalation and exhalation cycles.
As such, with reference to
Actuation of the droplet delivery device is initiated at the start of an inhalation cycle. The droplet delivery device can be battery powered and self-initiating, breath actuated or connected to electronics that are part of the ventilator. The system may be configured so that dosing frequency and duration may be set either within the ventilator or the device. Similarly, droplet ejection timing and duration can be determined by the device or initiated by the ventilator. For example, the device may be programmed to dispense for half a second once every ten breaths on a continuous basis or perhaps once a minute. A device may operate in a standalone manner or communicate the timing of dispenses and flowrates to the ventilator by a direct electrical connection or via Bluetooth or a similar wireless protocol.
Another aspect of the disclosure provides a system which may also be used with conventional portable CPAP machines to deliver therapeutic agents, e.g., where continuous or periodic dosing during the course of the night is valuable. In another embodiment, the droplet delivery devices of the disclosure many be used in connection with a portable CPAP machine to prevent and treat cardiac events during sleep.
Typically CPAP machines use a mask to supply positive air pressure to a patient while sleeping. Applications of the droplet delivery devices in conjunction with CPAP machines may provide an efficient method for continuous dosing of therapeutic agents such as antibiotics, cardiac medications, etc., for outpatient treatment of diseases, conditions, or disorders, such as pneumonia, atrial fibrillation, myocardial infarction, or any disease, condition, or disorder where continuous or periodic nighttime delivery of a medicine is desired.
In sleep apnea (SA) there are periods of not breathing and an associated decline in blood oxygen level. Not surprisingly, cardiac failure or “heart attacks” are associated with sleep apnea. This association is thought to be due to both the stress on the heart related to low oxygen levels and the increased stress on the heart as the body requires increased blood pressure and cardiac output from the heart. Additionally, there is increased risk of sleep apnea in older and overweight adults. Thus those with SA have a higher risk of heart attacks than the general population because the SA stresses the heart and because the risk factors associated with SA are very similar to the risk factors for heart attacks.
The Journal of New England in 2016 published a four-year study of the effects of CPAP on 2700 men with sleep apnea and found that CPAP significantly reduced snoring and daytime sleepiness and improved health-related quality of life and mood. (R. Doug McEvoy, et al. CPAP for Prevention of Cardiovascular Events in Obstructive Sleep Apnea, N. ENGL. J. MED. 375; 10 nejm.org Sep. 8, 2016). However, the use of CPAP did not significantly reduce the number of cardiac events. The article noted that “Obstructive sleep apnea is a common condition among patients with cardiovascular disease, affecting 40 to 60% of such patients.”
Many of these cardiac events can be lessened by administration of the proper medication. For example, beta blockers such as Metoprolol can lessen atrial fibrillation and the effects of myocardial infarction to sufficient extent as to prevent death in such an episode.
In certain aspects of the disclosure, the need to lessen adverse cardiac events in the population of people using CPAP devices by sensing the presence of the event and administering an ameliorating drug via pulmonary delivery is addressed. Specifically, a cardiac event may be detected by conventionally available means to detect and evaluate cardiac condition. These include heart rate monitors (such as electrical sensors held in place by an elastic band across the chest or optical monitoring at the earlobe, finger or wrist), automated blood pressure cuffs, or blood-oxygen saturation monitors on the finger or ear). When the monitor detects an adverse condition a specific dose of appropriate drug is administered by a droplet delivery device of the disclosure via the CPAP tube or mask so that the drug is inhaled and carried to the blood stream via deep inhalation into the lung. Pulmonary administration is optimized both by the generation of droplets less than 5 microns in size and delivery of the droplets at the beginning of an inhalation cycle.
Referring to
Other diseases commonly associated with sleep apnea, use of a mechanical ventilator, or a CPAP machine may also benefit from a system which non-invasively monitors patient condition and provides pulmonary administration of the appropriate ameliorating medication via a droplet delivery device of the disclosure. For example, those with diabetes frequently are concerned that low blood sugar from a slight insulin overdose will lead to unconsciousness. In this case, abnormally low heartrate, breathing or blood pressure can be detected and sugar or insulin administered via droplets to the pulmonary system.
Referring to
Droplet size distribution and related functionality was evaluated for exemplary droplet delivery devices of the disclosure, including Anderson Cascade Impactor testing, total drug mass output rates, total drug respirable mass, delivery efficiencies and reproducibility.
Test Design
A study was conducted at ARE Labs, Inc. to evaluate the aerosol characteristics and delivered dose of Albuterol sulfate using the Pneuma™ inhaler device. The study was designed to evaluate device performance of a single Pneuma™ inhaler. A series of three (3) individual tests were conducted with a new disposable drug cartridge for each test. The testing platform utilizes an eight-stage nonviable Anderson Cascade Impactor (Thermo Fisher Scientific; Waltham, Mass.) equipped with a calibrated AALBORG model GFM47 mass flow meter (AALBORG Instruments and Controls; Orangeburg, N.Y.) for flow rate measurement. A valved Gast rotary vane vacuum pump (Gast Manufacturing; Benton Harbor, Mich.) was used to
A droplet delivery device of the disclosure similar to that shown in
The cascade impactor testing procedure involved fitting the mouthpiece into the Impactor USP throat with a mouthpiece connection seal. The vacuum pump supplying sample air flow to the cascade impactor was turned on and the pump control valves adjusted to supply 28.3 L/min total flow through the impactor and inhaler body during aerosol tests.
At the initiation of each test, a new reservoir was filled with 750 μl of the stock Albuterol sulfate solution with a calibrated micropipette. The device was connected to the impactor USB throat, turned on, and actuated ten (10) times for each test. At the conclusion of the test period, the device, impactor, and dilution air sources were turned off. The i mouthpiece was rinsed in order to extract drug, and all stages of the cascade impactor were rinsed with a quantity of appropriate solvent (HPLC mobile phase). Extracted samples were placed in labeled and sterile HPLC vials, capped, and analyzed for drug content via HPLC with UV detection. The mouthpiece was extracted of residual drug and analyzed for drug content via HPLC to measure mouthpiece drug deposition in relation to the total collected on the impactor stages.
All system flow rates and impactor sample flows were monitored throughout each test period. Following each test, the impactor slides were placed in labeled sterile Petri dishes, and impactor stages were extracted of drug using 2 ml of mobile phase applied with a calibrated micropipette. All extracted samples from the mouthpiece and impactor were placed in labeled sterile amber HPLC sample vials, and stored refrigerated at approximately 2° C. until HPLC analysis.
Impactor collection stages for all tests were rinsed with DI water and ethanol, and air dried prior to each inhaler test trial to avoid contamination. A new inhaler drug cartridge was used for each of the three individual tests.
Drug Analysis
All drug content analysis was performed using a Dionex Ultimate 3000 nano-HPLC equipped with a Dionex UVD-3000 multi-wavelength UV/VIS Detector using a micro flow cell (75 um×10 mm path length, total analytical volume 44.2 nl). The column used for the albuterol sulfate was a Phenomenex Luna (0.3 mm ID×150 mm) C18, 100A (USP L1) column with a column flow rate of 6 μl/min at a nominal pressure of 186 bar. Total HPLC run time was 6 minutes per sample with approximately 5 minutes flush between each sample. Sample injection was performed with a 1 μl sample loop in full loop injection mode. Detection was with UV at 276 nm for albuterol sulfate.
HPLC Method and Standards
US Pharmacopeial monograph USP29nf24s_m1218 was followed as a reference method for analysis of albuterol sulfate. Briefly, the method involved dilution of an appropriate formulation of albuterol sulfate in mobile phase; 60% buffer and 40% HPLC grade methanol (Acros Organics). Buffer formulation contains reverseosmosis filtered deionized water with 1.13 gr of sodium 1-hexanesulfonate (Alfa Aesar) in 1200 ml of water, with 2 ml glacial acetic acid (Acros Organics) added. The mobile phase solution was mixed and filtered through a 0.45 um filter membrane. The final mobile phase is a 60:40 dilution of Buffer: MEOH.
Statistical Analysis
Mean and standard deviation were calculated for all triplicate trial sets for each component of: inhaler drug fill, total delivered dose, course particle dose, course particle fraction, respirable particle dose, respirable particle fraction, fine particle dose, fine particle fraction, aerosol MMAD and GSD. The number of trials provided for 95% confidence levels for all data sets.
Results
The table below provides a summary of the mass fraction of droplets collected on each droplet size stage of the Anderson Cascade Impactor testing (Albuterol, 0.5%, Anderson Cascade, 28.3 lpm, 10 actuations). As shown, over 75% of the droplets of an average diameter of less than about 5 μm, and over 70% have an average diameter of less than about 4 μm.
The table below provides an alternative format of the summary of Cascade impactor testing results, providing the results based on likely area of droplet impact in the mouthpiece/throat/coarse, respirable droplets, and fine droplets (Albuterol, 0.5%, Anderson Cascade, 28.3 lpm, 10 actuations).
An in vitro study was conducted to evaluate and compare the droplet delivery device of the present disclosure with two predicated devices, the Combivent® Respimat® inhaler (Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield Conn.) and the PROAIR® HFA (Teva Respiratory, LLC Frazer, Pa.). Initially, with reference to
The devices were tested dosing Albuterol sulfate aerosol size distribution and mass delivery characteristics. As described herein, the droplet delivery device of the disclosure is a breath-actuated piezoelectric actuated device with removable and replaceable reservoir. In this example, the reservoir is designed to contain a therapeutic inhalation drug volume to provide 100-200 breath actuated doses per use. The predicate device Combivent Respimat is a propellant free, piston actuated, multidose metered inhaler, while the ProAIr HFA device is a CFC free, propellant based metered dose inhale.
A single test device body, and three (3) reservoir/ejector mechanism modules were tested. All predicate devices were tested in triplicate, for a total nine (9) Cascade Impactor trials. The devices of the disclosure were tested in triplicate with a new drug reservoir charged with 750 μl of 0.5% Albuterol sulfate for each of the three (3) tests.
Particle size distributions were measured using the Anderson Cascade Impactor (ACI) sampling at a constant 28.3 lpm during each test. The Anderson Cascade Impactor test is as described above in Example B, and can be used to determine the coarse particle mass, coarse particle fraction, respirable particle mass, respirable particle fraction, fine particle mass, and fine particle fraction of test aerosols. ACI data can also be used to calculate the Mass Median Aerodynamic Diameter (MMAD) and Geometric Standard Deviation (GSD) of the aerosol size distribution. Droplet classifications are defined as following: Coarse particle fraction, >4.7 um; Respirable particle fraction, 0.4-4.7 um; Fine particle fraction, <0.4 um.
The predicate Combivent® Respimat® inhaler was tested using Combivent® Respimat® cartridges containing 20 mcg ipratropium bromide and 100 mcg albuterol equivalent to 120 mcg dose of albuterol sulfate delivery per actuation. The predicate PROAIR® HFA inhaler was evaluated with cartridges containing 108 mcg albuterol sulfate equivalent to 90 mcg delivered dose per actuation, while the droplet delivery device of the disclosure was evaluated using albuterol sulfate at a concentration of 5000 ug/ml equivalent to 0.5% albuterol and 85 mcg delivered dose per actuation.
Results from cascade impactor test trials for each inhaler tested in triplicate for Albuterol sulfate are as follows (
Average MMAD for: Test Device, 1.93±0.11, Combivent® Respimat®, 1.75±0.19, and PROAIR® HFA 2.65±0.05 m for dispensing Albuterol sulfate.
Average GSD, for: Test Device: 1.96±0.16, Combivent® Respimat®, 2.79±0.25, and PROAIR® HFA, 1.48±0.02.
A summary and comparison of Cascade Impactor Testing of the test device, Combivent Respimat® and Proair® HFA inhalers is shown in the tables below and in
For the Test device, 68.7%±3.2%,
Combivent® Respimat®, 57.3%±10.5, and
PROAIR® HFA, 65.2%±2.4%.
Using an exemplary ejector device of the disclosure (test device), a cross over clinical trial was conducted comparing the acute bronchodilatory effects of the test device using albuterol sulfate and ipratropium bromide versus no treatment in a group of patients with chronic obstructive pulmonary disease.
Up to 75 patients with COPD will be enrolled. To be eligible for the study, subjects at visit 1 must: 1) be previously diagnosed with COPD; 2) have at least a 10 pack year smoking history; 3) be prescribed one or more inhaled bronchodilators; 4) exhibit post bronchodilator FEV1≥25% and <70% predicted normal value using appropriate reference equations.
The study is a crossover, single center, 1 day lung function study to measure the acute bronchodilation effect of standard dose albuterol sulfate and ipratropium bromide using an test device of the disclosure in a group of COPD patients.
Subjects may undergo up to a 1 week screening period. If the patient is not using long acting beta agonists or long acting muscarinic antagonists and has not used a short acting bronchodilator in the previous 6 hours, no washout period is necessary and can immediately proceed with visit 2. If the subject is using a long acting beta agonist they will be washed out for 48 hours. If the subject is using a long acting muscarinic antagonist the washout period will be one week. During the washout period subjects will be allowed to continue to use inhaled corticosteroids (ICS), short acting beta agonists (SABA), short acting muscarinic antagonists (SAMA), leukotriene inhibitors, and phosphodiesterase 4 inhibitors. Subjects experiencing COPD exacerbations during the washout period will be excluded from the trial. Subjects who successfully complete the screening period will be included in the trial.
As described herein, the test devices include piezoelectric actuated ejector mechanisms integrated with reservoir. The reservoir mounts to a device housing. The device housing has 2 areas 1) a mouthpiece tube and 2) a handle. The patient breathes in through the mouthpiece tube to activate the ejector mechanism. The mouthpiece tube detaches from the housing and can be sterilized and reused or disposed of after patient use.
The primary efficacy endpoints will include change in FEV1 during 2 time periods: the 20 minutes before receiving a dose of albuterol sulfate and ipratropium bromide using the ejector device of the disclosure, and the 20 minutes after receiving a dose of albuterol sulfate and ipratropium bromide from the ejector device of the disclosure. Safety endpoint will include vital signs and changes in FEV1. The statistical analysis will include an analysis of the change in FEV1 using T-tests.
Interim results demonstrate the use of the ejector device of the disclosure provides a significant bronchodilatory effect versus no treatment. For instance, with partial enrolment, the following average FEV1 readings were obtained:
As shown in the table above, treatment with the ejector device of the disclosure improved FEV1 by an average of about 260-275 cc. This improvement is 1.2 to 2 times the increase in broncodilatory effect typically observed using standard manual inhalers with the same dose of active drug.
Using an exemplary droplet delivery device of the disclosure (test device), a cross over clinical trial was conducted comparing the acute bronchodilatory effects of the test device using albuterol sulfate versus the ProAir® HFA Inhaler in a group of patients with chronic obstructive pulmonary disease (COPD).
Up to 75 patients with COPD will be enrolled. To be eligible for the study, subjects at visit 1 must: 1) be previously diagnosed with COPD; 2) have at least a 10 pack year smoking history; 3) be prescribed one or more inhaled bronchodilators; 4) exhibit FEV1 <70% or at least 10% lower than the predicted normal value using appropriate reference equations.
This is a crossover, single center, 2 to 3 day lung function study to measure the acute bronchodilation effect of standard dose albuterol sulfate using the test device in a group of COPD patients and to compare this to the same drug given with a predicate device, the ProAir HFA Inhaler, but at half the dose administered with the predicate device.
Subjects may undergo up to a 1 week screening period. If the patient is not using long acting beta agonists or long acting muscarinic antagonists and has not used a short acting bronchodilator in the previous 6 hours, no washout period is necessary and can immediately proceed with visit 2. If the subject is using a long acting beta agonist, they will be washed out for 48 hours. If the subject is using a long acting muscarinic antagonist, the washout period will be up to one week. During the washout period subjects will be allowed to continue to use inhaled corticosteroids (ICS), short acting beta agonists (SABA), short acting muscarinic antagonists (SAMA), leukotriene inhibitors, and phosphodiesterase 4 inhibitors. Subjects experiencing COPD exacerbations during the washout period will be excluded from the trial. Subjects who successfully complete the screening period will be included in the trial.
As described herein, the test devices include piezoelectric actuated ejector mechanisms integrated with reservoir. The reservoir mounts to a device housing. The device housing has 2 areas 1) a mouthpiece tube and 2) a handle. The patient breathes in through the mouthpiece tube to activate the ejector mechanism. The mouthpiece tube detaches from the housing and can be sterilized and reused or disposed of after patient use.
The primary efficacy endpoints will include change in FEV1 during 2 time periods: the 20 minutes before receiving a dose of albuterol sulfate and the 20 minutes after receiving a dose of albuterol sulfate using the test device of the disclosure. Safety endpoint will include vital signs and changes in FEV1. The statistical analysis will include an analysis of the change in FEV1 using T-tests.
Results demonstrate the use of the test device of the disclosure provides a significant bronchodilatory effect versus no treatment, and a similar but slightly improved bronchodilatory effect versus treatment with twice the dose using a predicate device, the ProAir HFA device. More particularly, there was a statistically significant improvement in FEV1 (120 ml) with the device at a 100 microgram dose of albuterol compared to no treatment. Further, it was unexpectedly found that the average improvement was 11.9 ml greater than the improvement seen with twice the dose of 200 micrograms using the predicate device, the ProAir HFA inhaler. In this regard, the test device of the disclosure was able to achieve a similar but slightly improved clinical efficacy at half the dose of the predicate device. The test device was able to delivery concentrated doses of a COPD medication and provide meaningful therapeutic efficacy, as compared to standard treatment options.
The below tables provide detailed data:
Using an exemplary droplet delivery device of the disclosure, testing is conducted to verify that large molecules including epidermal growth factor receptor (EGFR) monoclonocal antibody, bevacizumab (Avastin), adalimumab (Humira) and etanercept (Enbrel) is not denatured or degraded by ejection through the device of the disclosure, and to verify that local pulmonary delivery and/or systemic delivery of the active agent is achieved.
Droplet Characterization:
To verify droplet generation, droplet impactor studies may be performed, as described herein.
Gel Electrophoresis:
To determine the stability of active agent after droplet generation, the generated stream of droplets including the active agent is collected and the molecular weight of the active agent is verified using gel electrophoresis. Gel electrophoresis will show that there is negligible change in the electrophoretic mobility, and hence the molecular weight, of the post-aerosol active agent from that of the control, i.e., whole EGFR antibodies, bevacizumab, adalimumab, or etanercept. The gel will also show that is no evidence of smaller fragments of the protein on the gel, further confirming that the aerosol generation will not cause any appreciable protein degradation. In addition, the gel will show no apparent aggregation of the antibody or protein, which is significant as many inhalation devices have been reported to be prone to protein aggregation and hence unsuitable for the pulmonary delivery of large macromolecules such as proteins and antibodies.
Size Exclusion Chromatography (SEC):
Alternately, to determine the stability of active agent after droplet generation, the generated stream of droplets including the active agent may be collected and SEC-HPLIC may be employed to monitor for any changes in large molecule aggregation and protein fragment content. Soluble protein aggregates and protein fragment content may be calculated by comparing respective peak area under the SEC-HPLC curve of dispensed protein solutions with controls (solutions remaining in the device reservoir).
Drug solutions for testing include Enbrel, (ENBREL® single-use prefilled syringes in 25 mg (0.51 mL of a 50 mg/mL solution of etanercept), and insulin, (Humalog, 200 units/ml, 3 ml kwikpens)
ENBREL® (etanercept) is a dimeric fusion protein consisting of the extracellular ligand-binding portion of the human 75 kilodalton (p75) tumor necrosis factor receptor (TNFR) linked to the Fc portion of human IgG1. The Fc component of etanercept contains the CH2 domain, the CH3 domain and hinge region, but not the CH1 domain of IgG1. Etanercept is produced by recombinant DNA technology in a Chinese hamster ovary (CHO) mammalian cell expression system. It consists of 934 amino acids and has an apparent molecular weight of approximately 150 kilodaltons.
SEC is performed with a Yarra™ 3 um SEC-2000 LC column 300×7.8 mm, SecurityGuard cartridge kit and SecurityGuard cartridges GFC-2000, 4×3 mm ID. Fifty microliters of Enbrel from the syringe (ENBREL® single-use prefilled syringes in 25 mg/0.51 mL of a 50 mg/mL solution of etanercept) is diluted (4:1) (4 parts, 200 mcl of the mobile phase buffer solution to 1 part, 50 mcl Enbrel from syringe). Fifty microliter of the diluted Enbrel is injected and separation was performed at a flow rate of 1.0 ml/min. The mobile phase buffer system included a PHOS. BUFF. SALINE. (PBS) solution and 0.025% NaN3, pH 6.8. UV detection is performed at 280 nm.
To calculate and compare effects of droplet generation through an ejector mechanism of the disclosure, the total area under the curve of the UV signal at 280 nm versus elution time for controls is compared with the aerosolized samples, which is set to 100%.
Fifty microliters (mcl) of insulin, (Humalog, 200 units/ml, 3 ml Kwikpens) is directly drawn from the Kwikpen and injected into the SEC column for analysis while 200 mcl of the Kwikpen solution is directly injected into the ampule/cartridge before actuation and aerosol generation with the test device. Aerosol collection and SEC is performed in a similar fashion as for the Enbrel analysis and aerosol collection.
An ampule/cartridge is filled with either 0.20 ml of Enbrel® (50 mg/ml) diluted 4:1 (10 mg/ml)(4 parts (200 mcl) of PBS and 0.025% NaN3 and 1 part (50 mcl of Enbrel solution from the syringe). After 20 actuations and aerosolization, about 150 mcl of the aerosolized Enbrel solution is recovered and collected in the polypropylene tube located below the ejector mechanism. The control consists of the diluted Enbrel solution, 50 mcl of which is injected into the SEC column for analysis.
Insulin solutions from a Humalog, 200 units/ml, 3 ml Kwikpen is drawn with a syringe and 200 mcl is injected directly into the reservoir/ejector mechanism module and mounted onto a test device before actuation. Aerosol emerging from the test device is collected by placing a 0.5 ml polypropylene test tube directly below the aperture plate. Twenty actuations aerisolization resulted in the recovery of about 150 mcl of the aerosol insulin spray. Fifty microliters of the collected aerosol spray is injected onto the SEC column for analysis, while 50 mcl of the Kwikpen insulin solution is injected onto the SEC column for control samples.
Results: Enbrel
Referring to
These data demonstrate that the test device can deliver 95.4% of Enbrel that is structurally unchanged after delivering an aerosol dose, while only 4.6% of the dose leads to formation of molecular fragments with elution times of 13 and 25 minutes.
Gravimetric analysis was performed by weighing the Enbrel solution filled ampule before and after dosing. The average of five doses (actuations) were analyzed with an average of 4.25 mg+/−0.15 mg. The total delivered dose of Enbrel per actuation is therefore 42.5 mcg per actuation. In comparison, actuation of distilled water with the same ampule resulted in a delivered dose of 9.26 mg.+/−1.19 mg.
Results; Insulin
Referring to
These data demonstrate that the test device can deliver 97.5% of the ejected dose of Insulin that is structurally unchanged while 2.5% of the ejected dose forms a fragment which elutes at ˜25 minutes.
Gravimetric analysis was performed by weighing the Insulin solution filled ampule before and after dosing. The average of five doses (actuations) were analyzed with an average of 5.01 mg+/−0.53 mg. The total delivered dose of Insulin per actuation is therefore 34.8 mcg per actuation.
Antibody/Protein Binding Assay:
The activity of the aerosolized antibody or protein is demonstrated by testing its ability to bind to its antigen or target on a cell surface, i.e., EGFR, TNFα, etc. Flow cytometry data of cells incubated with either aerosolized or non-aerosolized active agent will reflect activity. Specifically, the data will show a shift in the fluorescence intensity of the cells incubated with non-aerosolized fluorescently labelled active agent compared to that for the untreated cells. A similar shift will be obtained with cells incubated with aerosolized active agent, suggesting that the post-aerosolized active agent retains its immunoactivity and hence its ability to bind to its target receptor on the cell surface.
Clinical/In Vivo Testing:
Using an exemplary ejector device of the disclosure, as generally shown in
The present application claims benefit under 35 U.S.C. § 119 of: U.S. Provisional Patent Application No. 62/331,328, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on May 3, 2016; U.S. Provisional Patent Application No. 62/332,352, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on May 5, 2016; U.S. Provisional Patent Application No. 62/334,076, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on May 10, 2016; U.S. Provisional Patent Application No. 62/354,437, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Jun. 24, 2016; U.S. Provisional Patent Application No. 62/399,091, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Sep. 23, 2016; U.S. Provisional Patent Application No. 62/416,026, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Nov. 1, 2016; U.S. Provisional Patent Application No. 62/422,932, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Nov. 16, 2016; U.S. Provisional Patent Application No. 62/428,696, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Dec. 1, 2016; U.S. Provisional Patent Application No. 62/448,796, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Jan. 20, 2017; and U.S. Provisional Patent Application No. 62/471,929, entitled “DISPOSABLE PULMONARY DRUG DELIVERY APPARATUS AND METHODS OF USE,” filed on Mar. 15, 2017. The content of each application is incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2017/030921 | 5/3/2017 | WO | 00 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2017/192774 | 11/9/2017 | WO | A |
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