Abstract:
A device for delivering medications with hydroflouroalkane propellant driven metered-dose inhalers (MDIs). The device includes a collapsible bag to which is attached a bidirectional mouthpiece and an adaptor that receives the MDI. The mouthpiece contains a reed that functions as an audible signal and a screen to prevent inhalation of unwanted particles. When the MDI is triggered it discharges the medication into the collapsible bag which is then inhaled by the user through the mouthpiece. This collapses the bag. The reed emits an audible sound if the user inhales above a predetermined flow rate to maximize medication delivery and ensure dose-to-dose consistency.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based on and claims the priority of U.S. provisional patent application Ser. No. 62/126,973 filed Mar. 2, 2015. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to inhalations systems for delivering a dose of aerosolized medication from metered-dose inhaler devices, for inhalation by a patient. 
       BACKGROUND AND SUMMARY OF THE INVENTION 
       [0003]    Delivery of pharmaceuticals via inhalation has long been considered the standard of care for the treatment patients with acute and chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (“COPD”). Over the past 50 years, metered-dose inhalers (“MDIs”) have become the mainstay of inhaled treatment for such patients. Experience clearly shows that while widely prescribed, many patients cannot or will not use MDIs as intended. 
         [0004]    Suboptimal MDI technique contributes to poor lung deposition of medication, poor disease control, adverse asthma and COPD outcomes, and increased medical costs. Studies demonstrate the inability of both patients and healthcare providers to properly use MDIs. Due to the inability of patients to properly use MDIs, a number of devices have been proposed to assist in MDI use. In laboratory test conditions, many devices have appeared to improve MDI aerosol delivery to the lower airways; however, outside of the laboratory, many patients cannot consistently use these devices as intended. Furthermore, for many of the currently available MDI spacer and holding chamber assist devices, it is problematic for the device users to determine if they fully inhale the complete dose following MDI actuation, and difficult for users to master consistent inhalation technique. 
         [0005]    Once an MDI canister is triggered, the most important patient centered factors that relate to optimal lung delivery of medication are: (1) initiation of inhalation prior to 80% of total lung capacity (within approximately the first 1-2 seconds after medication is aerosolized), and (2) that the user generate a sufficiently low inspiratory flow rate to effective deliver proper sized aerosol particles into the lung alveoli. The subjective terms “long” or “slowly” are common manufacturer&#39;s instruction on MDI medication inserts but these terms have been of little value in ensuring proper patient inhalation technique. Devices which do or not have an effective inspiratory flow signal or fail to provide effective feedback regarding complete dose inhalation may result in medication dosing to the lung that is not constant dose-to-dose or patient-to-patient. 
         [0006]    Prior art devices were designed to work with the previous generation of chlorofluorocarbons (“CFC”) MDI devices only. Some of these prior art devices has a built in one size fits all actuator in the mouthpiece. The current hydrofluoroalkane (“HFA”) propellant containing MDIs have a large number of different actuator orifices, so that a single actuator mouthpiece will not adequately function for optimal delivery of the various HFA MDI medications. These prior art devices completely fail to adequately address these elements and do not match optimal characteristics of the inventive device. For example, the prior art devices lack the proper actuator design for proper and efficient MDI particle size generation with current HFA MDI canisters and are designed only for use with prior CFC propellant containing MDIs. Furthermore, many current HFA MDI canisters cannot be used in the prior art devices as the canisters cannot fit into the device mouthpiece, essentially making the device/canister completely non-functional. 
         [0007]    Several of the prior art devices lack an inspiratory flow reed and fail to provide any type of signal regarding the users inspiratory flow rate. The inspiratory flow rate is the most critical technique factor which determines the effectiveness of inhaled medication delivery from an MDI canister after the MDI is triggered. Other prior art devices have an inefficiently designed actuator orifice diameter, which produces suboptimal MDI particle size generation, and thus a less efficient device compared to the instant inventive device. 
         [0008]    The shortcomings of the prior art devices are that they either lack optimal actuator sizing for the different HFA-MDI formulations, inspiratory flow signal (i.e., not capable of ensuring puff-puff dose equivalency), an easy means for determining if medication is fully inhaled, or have a complicated mechanism presenting difficulty to patients to operate. Manufacturers fail to recognize importance of a properly designed inspiratory flow rate signal for user effective device use and fail to have flow signals which function outside the laboratory for optimal patient use. 
         [0009]    Applicant&#39;s invention addresses the shortcomings of the prior art by providing a simple, efficient, easy to use device for patients to consistently deliver HFA containing medications from metered-dose inhaler MDIs. Applicant&#39;s device insures consistent puff-to-puff delivery of inhaled medications via an adaptor optimized for HFA MDI medications, and an effective inspiratory flow reed signal. The device includes a collapsible bag to which is attached a bidirectional mouthpiece and an adaptor that receives the MDI medication. The mouthpiece contains a reed that functions as an audible signal and a screen to prevent inhalation of unwanted particles. When the MDI is triggered it discharges the medication into the collapsible bag. The medication is inhaled from the collapsible bag, through the mouthpiece, directly into the respiratory tract, collapsing the bag. The reed emits an audible sound if the user inhales above a predetermined rate to maximize medication delivery and ensure dose-to-dose consistency. The user has instant feedback regarding correct inhalation from MDI medication regarding: (1) whether each dose of medication is completely inhaled (the bag fully collapses upon complete inhalation), and (2) whether each dose is inhaled at a rate to achieve efficient lower airway aerosol medication delivery (a whistle sounds of the user breathes in too fast). 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is an exploded view of the inventive delivery device for metered dose inhalers. 
           [0011]      FIG. 2  is a top view of the top end cap of the device with the mouthpiece and adaptor attached. 
           [0012]      FIG. 3  is a top perspective of the top end cap with the adaptor and mouthpiece attached. 
           [0013]      FIG. 4  is a side view of the mouthpiece. 
           [0014]      FIG. 5  is a rear perspective view of the mouthpiece showing the screen inserted into the mouthpiece. 
           [0015]      FIG. 6  is top view of the reed. 
           [0016]      FIG. 7  is a bottom view of the reed. 
           [0017]      FIG. 8  is a top perspective view of the adaptor. 
           [0018]      FIG. 9  is a bottom perspective view of the adaptor. 
           [0019]      FIG. 10  is a cross sectional view of the adaptor taken along lines  10 - 10  of  FIG. 8 . 
           [0020]      FIG. 11  is a top perspective view of the top end cap. 
           [0021]      FIG. 12  is cross sectional view taken along line  12 - 12  of  FIG. 11 . 
           [0022]      FIG. 13  is a bottom view of the bottom end cap. 
           [0023]      FIG. 14  is a top view of the bottom end cap. 
           [0024]      FIG. 15  is a front perspective view of the collapsible bag. 
           [0025]      FIG. 16  is a front perspective view of the collapsible bag when in a horizontal position. 
           [0026]      FIG. 17  is a front perspective view of the assembled device in the vertical position. 
           [0027]      FIG. 18  is a perspective view of the inventive device in the horizontal position with the MDI actuator inserted into the adaptor. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0028]    Turning first to  FIG. 1  there is illustrated an exploded view of the delivery device for metered dose inhalers  20 . There is a mouthpiece  22  that has a reed  24  inserted into a lower end  26  of the mouthpiece  22 . The mouthpiece  22  is inserted into a top end cap  28  through opening  30 . The opening  30  has two opposite rectangular slots  32  which receive locking tabs  34  at the lower end  26  of the mouthpiece  22  (seen in  FIG. 5 ). 
         [0029]    The top end cap  28  also has an upstanding collar  36  angularly disposed with respect to the top planar surface of the top end cap  28 . There are a pair of vertically disposed keyways  38  cut into the wall of the upstanding collar  36 . An MDI adaptor  40  is mounted on the collar  36 . There are keys  42  ( FIG. 9 ) that are received in the keyways  38  to properly align the MDI adaptor  40  with the collar  36 . There is a channel  41  in the MDI adaptor that receives the collar  36  in tight engagement to firmly, but releasably retain the MDI adaptor  40  on the collar  36 . 
         [0030]    A collapsible flexible bag  44  is located below the top end cap  28 . The collapsible bag is preferably made from low density polyethylene (“LDPE”) but other similar materials are also available. At the bottom of the LDPE bag  44  is a bottom end cap  46 . The top end cap  28  has a circumferential collar that closely receives the top of the LDPE bag  44 . The bottom end cap  46  has a similar circumferential collar that receives the bottom of the LDPE bag  44 . The fit between the top cap  28  and the bag  44  and the bottom end cap  46  and the bag  44  is snug so that it forms an air tight seal between the caps and the bag. 
         [0031]    As seen in  FIG. 2  the mouthpiece  22  has a screen  48  mounted in its central channel.  FIGS. 2 and 3  illustrate the mouthpiece  22  and MDI adaptor  40  mounted on the top end cap. An air tight seal is provided between the mouthpiece  22  and the top end cap  28  and the MDI adaptor  40  and the upstanding collar  36 . 
         [0032]      FIGS. 4 and 5  more clearly illustrate the mouthpiece  2 . The locking tabs  34  are clearly illustrated at opposite sides of the bottom of the mouthpiece  22 . As seen in  FIG. 5  there is a reed attachment internal collar or site  50  that receives and positions the reed  24  within the bottom of the mouthpiece  22 .  FIGS. 6 and 7  illustrate the reed  24 . There are a pair of vibrating members  52  mounted in slots  54 . One end of the each of the vibrating members  52  is fixed to the reed body while the opposite end is free to vibrate. Other types of reed designs can be used as is commonly known in the art. The purpose of the reed is to vibrate and produce an audible sound if the air flow past the reed exceeds a preset level. 
         [0033]      FIGS. 8-10  illustrate the MDI adaptor. The adaptor  40  is preferably made from a flexible material that is sufficiently rigid to retain its shape when inserted onto the collar  36  but has an innermost ring  56  that is flexible enough to receive various size metered dose inhalers. The MDI should be snugly received in the innermost ring  56  so that substantially an air tight seal is formed between the innermost ring  56  and the MDI adaptor  40 . 
         [0034]      FIG. 11  clearly illustrates the opening  30  with the slots  32  cut in the top end cap  28 . These receive the locking tabs  34  in the bottom of the mouthpiece  22 . Once the locking tabs  34  are inserted, the mouthpiece is rotated so that the locking tabs  34  firmly lock the mouthpiece to the top end cap  28 . The collar  36  is also shown with the keyways  38 . These received the keys  42  in the underside of the MDI adaptor  40 . 
         [0035]      FIG. 12  is a cross sectional view of a portion of the MDI adaptor  40  mounted to the collar  36  which in turn is mounted to or integrally formed with the top end cap  28 .  FIGS. 13 and 14  illustrate bottom end cap  14 . As seen in  FIG. 14  there is an upstanding collar or rim that closely receives in an air tight fitting the bottom of the flexible bag  44 .  FIGS. 15 and 16  illustrate the cylindrical shape of the LDPE flexible bag  44 . 
         [0036]      FIG. 17  illustrates the assembled delivery device for metered dose inhalers  20 . The mouthpiece  22  and MDI adaptor  40  and fitted onto the top end cap  28 . Inside of the mouthpiece  22  are the reed  24  and screen  48 . The top end cap  28  is securely fitted on the top of the LDPE flexible bag  44 . The bottom end cap  46  is securely fitted onto the bottom end cap  46 . 
         [0037]      FIG. 18  is similar to  FIG. 17  except that an MDI actuator  58  is inserted into the MDI adaptor  40 . The HFA MDI canister is inserted into the MDI actuator. 
         [0038]    To use the device  20 , the mouthpiece  22  is inserted via the locking tabs  34  into slots  32  and rotated to lock the mouthpiece to the top end cap  28 . The user inserts an MDI canister into the MDI actuator  58  which aligns it with the MDI adaptor orifice in the top end cap  28 . The user opens the bag  44  fully. User then depresses the MDI canister, which then generates flow of medication into the LDPE bag  44 . The user inhales through mouthpiece  22 , generating negative pressure in bag  44  and causing aerosolized medication to flow into the user&#39;s respiratory tract, thereby collapsing the bag  44 . The inspiratory flow reed  24  signals if the user inhales above a predetermined flow rate, which is generally above 0.6 liter/sec. After inhalation and 10 second breathhold, the user manually opens and expands the bag  44  to allow for a subsequent MDI actuation cycle. The device  20  provides two indicators if the device is used properly. The first signal is a visual signal that indicates whether the user has fully inhaled the medication. This is indicated by the user seeing if the bag is fully collapsed. The second indicator is an audio signal indicating if the user incorrectly inhaled the medication. This is indicated by the reed in the device emitting a whistling or other audible sound if user inhales too fast for proper medication delivery to the lungs. 
         [0039]    Thus there has been provided a delivery device for metered dose inhalers for providing a drug to a user through inhalation that provides for the receipt of various sized MDI canisters. It also provides two indicators for the user to make sure that the full dose of medication is inhaled and that the rate of inhalation is not at a flow rate that exceeds recommended flow rates. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it in intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the claims