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Description  |
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FIELD OF INVENTION
This invention relates to an everting device for delivering a drug or other
pharmaceutical preparation in powder or aerosol form to an internal body
cavity. More particularly this invention relates to an everting toroid
device and methods for delivering a drug or the like to the urethral lumen
or other internal mucosal or absorptive surface.
BACKGROUND OF INVENTION
Everting sleeve devices for probing internal body cavities, for delivering
drugs in powder form to the surfaces of those cavities and for taking
samples from within the cavity are well known in the medical arts.
Attention is directed to U.S. Pat. Nos. 3,168,092 issued Feb. 2, 1965, No.
3,500,819 issued Mar. 17, 1970 and No. 3,589,356 issued Jun. 29, 1971, all
to Daniel Silverman, which are typical of the prior art everting sleeve
devices. Essentially, a cylindrical external casing is provided with a
long thin walled plastic tubing which is anchored at one end thereof to
the inside wall of the casing and extends along the inside of the casing.
The tubing may be open- or closed-ended. By application of external gas
pressure between the casing and the tubing, the tubing is forced to turn
on itself, or evert, and extend outwardly beyond the end of the casing.
Powdered drugs may be applied to the everting surfaces before use and
these will be deposited on the mucosa or walls of the body cavity as the
tubing extends. If an open-ended tubing is employed, samples of body
fluids or the like may be withdrawn through the extended tubing.
Withdrawal of the tubing may be effected by withdrawing the tubing in its
extended condition or by re-everting the tubing by pulling on an
internally mounted withdrawal cord or the like. These prior art devices,
while relatively effective, suffer from several serious disadvantages.
Firstly, considerable pressure is required to evert the tubing and in the
event that the tubing should fail during eversion considerable damage to
sensitive and delicate body tissues may result. Secondly, withdrawing an
extended tubing from a body cavity may cause considerable friction and
hence discomfort or pain to the patient. Everting the extended tubing by
means of an internal withdrawal cord or the like is cumbersome and not
very practical in the case of very thin long tubes. There is a need,
therefore, for an improved everting sleeve-type device for delivering
powdered drugs and the like to long narrow body passages, such as, but not
limited to, the urethra, bladder, vagina, anus, rectum and colon.
OBJECT OF THE INVENTION
An object of the present invention is to provide an improved everting
toroidal low-pressure sleeve type device for delivering drugs and the like
to internal body cavities. Another object of this invention is to provide
an everting toroidal sleeve-type device in combination with an aerosol
delivery device for delivery of drugs and the like to internal body
cavities.
Yet another object is to provide novel methods for delivery of
pharmaceutical compositions, such as drugs, to internal body cavities.
BRIEF STATEMENT OF INVENTION
By one aspect of this invention there is provided an apparatus for
delivering a pharmaceutical composition in fluid or solid form to the
lumen of an internal body cavity, comprising: a tubular housing member
having a first open end and a second end; an elongated flexible toroidal
member contained within said housing member and having an outer surface
portion thereof secured to said housing adjacent said first open end
thereof; and means adjacent said second end, contacting a surface portion
of said toroidal member, and adapted to move through said housing member
towards said first open end thereof so as to cause said toroidal member to
evert and extend outwardly from said first open end of said housing
member.
By another aspect of this invention there is provided an apparatus for
delivering a pharmaceutical composition in fluid or solid form to the
lumen of an internal body cavity, in combination a tubular housing member
having a first open end and a second end; an elongated flexible toroidal
member contained within said housing member and having an outer surface
portion thereof secured to said housing adjacent said first open end
thereof; means adjacent said second end, secured to an inner surface
portion of said toroidal member, and adapted to move through said housing
member towards said first open end thereof so as to cause said toroidal
member to evert and extend outwardly from said first open end of said
housing member; a second tubular housing member having a proximal end and
an open distal end; tubular means contained within said second tubular
housing having an open distal end and an aerosolized pharmaceutical
delivery chamber at a proximal end thereof; means to extend said tubular
means longitudinally outwardly from said open distal end of said second
tubular housing and to retract said extended tubular means back into said
second tubular housing; and valve means adjacent said delivery chamber to
dispense an aerosolized pharmaceutical contained in said delivery chamber
through said tubular means to said distal end thereof when said tubular
means is extended from said second housing member and is retracting
thereinto; wherein said tubular housing member and said toroidal member
are adapted to axially receive said tubular member when in said extended
position from said second tubular housing member.
By yet another aspect of this invention there is provided an apparatus
wherein said means to extend said tubular means includes slide means
adapted to cooperate with said second tubular housing member to extend
said tubular means longitudinally therefrom.
In an alternative aspect of this invention, there is provided a method for
delivering a pharmaceutical composition or mixture thereof to the lumen of
an internal body cavity, comprising: providing a tubular housing member
having a first open end and a second end; an elongated flexible toroidal
member contained within said housing member and having an outer surface
portion thereof secured to said housing adjacent said first open end; and
means adjacent said second end, contacting a surface portion of said
toroidal member, and adapted to move through said housing member towards
said first open end thereof; adhering a selected said pharmaceutical
composition to an inner surface of said toroidal member; and advancing
said means adjacent said second end through said housing member so as to
cause said toroidal member to evert into said internal body cavity and
thereby deposit said pharmaceutical composition therein.
The body cavity may be the urethra, bladder, vagina, anus, rectum, colon,
pharynx, or other suitable cavity of a subject in need of drug delivery
thereto. Preferably, the body cavity is the urethra, and more preferably,
the adult male urethra.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a top plan view of a drug delivery device according to one
embodiment of this invention, in closed position;
FIG. 2 is a top plan view of the device of FIG. 1 shown in extended
position;
FIG. 3 is a top plan view of an alternative embodiment of the invention, in
closed position;
FIG. 4 is a top plan view of the device of FIG. 3 shown in extended
position;
FIG. 5 is a top plan view of an aerosol drug delivery device of the present
invention, in closed position;
FIG. 6 is a side view of the device of FIG. 5;
FIG. 7 is a top plan view of the device of FIG. 5, shown in extended
position; and
FIG. 8 is a top plan view of the device of FIG. 7 shown during the
withdrawal and drug delivery phase of the cycle.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In FIG. 1 there is shown a flexible ring or toroid 1 made from a thin,
physiologically inert and acceptable thermoplastic film material, such as
silicone or polyurethane about 0.5 to about 50 .mu.m thick, which is
filled with a physiologically inert material 2, such as an isotonic saline
solution, a gas such as nitrogen or a gel, under relatively low pressure.
In some applications, such as, for example, delivery to the anus or
rectum, the film may be thicker in comparison to applications such as
delivery to the urethra, where the film is preferably about 0.5 to about
10 .mu.m. Toroid 1 is elongated in one dimension so that it has a length
which typically is about 5 to about 40 times the external diameter, but is
not limited thereto. Depending on the specific cavity, the diameter D is
preferable about 2 to about 20 mm. For example, for delivery of
vasodilating drugs to the male or female urethra, the toroid will
preferably have an outside diameter in the range of about 6 to about 8 mm,
which is the diameter of the adult urethra, and be up to about 30 cm long
so that it can be extended beyond the external part of the urethra, or
fossa naviculari (in the male) which is composed of squamous epithelium
cells and less absorptive, so as to reach the proximal urethra and, in
some applications, the bladder. Toroid 1 is mounted inside an applicator
tube 3 and secured at the open end 4 thereof by means of an adhesive 5 or
the like around the surface of toroid 1. At the other, preferably closed,
end 6 of the tube 3, a slide 7 is secured to the inner diameter or
internal lumen 8 of toroid 1 by adhesive 9. Slide 7 moves along a slot 10
in tube 3 a distance L. In use, the physician, health professional and/or
patient, places the tube 3 with the end 4 adjacent the distal urethra and
slides the slide 7 towards the end 4, thereby causing the toroid to
advance in a rolling action into the unopened urethra a distance L/2. The
tube wall that everts from the central lumen 8 to the outside will remain
stationary relative to both tube 3 and the wall of the urethra once it is
in place. This means that the urethra is opened by lateral pressure only
without sliding relative to the mucosa of the urethra, thereby
considerably reducing any discomfort to the patient. In an alternative
embodiment shown in FIGS. 3 and 4, an external plunger 21 rests against
the toroid 2 but is not secured thereto. The plunger may be L to 2L in
length. As the plunger is pushed in a distance L, the toroid everts a
distance L as well. It will be appreciated that the internal lumen 8 of
the toroid can be coated before insertion into the urethra with any
selected drug or other medicament, preferably in powder form with or
without a carrier therefor, so that, as the toroid everts into the
urethra, the drug is deposited directly onto the urethral mucosa for
direct absorption thereinto. The drug may be a salt, or even a base
compound, or may be coated on the device as separate components. In some
embodiments, such components may be relatively unstable in combination and
mix on contact with the urethral mucosa. Alternatively, an aerosol device
described in more detail hereinbelow may be inserted through the extended
toroid to deliver drugs to the proximal end of the uretha and to the
urethral mucosa as the device is withdrawn. Withdrawal of the toroid 1 is
simply effected by the user moving slide 7 from end 4 towards closed end 6
of tube 3, thereby causing toroid 1 to invert back to the original
position as shown in FIG. 1. Again, it is to be noted that there is no
sliding motion between the toroid 1 and the urethral mucosa, therefore
reducing friction to a minimum with increased patient comfort, and also
ensuring that the deposited drug is not removed from the deposit site.
Turning now to FIGS. 5-8, there is shown an aerosol device which may be
directly inserted into a body cavity, such as the urethra, but preferably
through or with the lumen of the everting toroid 1 of FIGS. 1 and 2. The
everting toroid 1 may have already been inserted into the body cavity, or
the toroid and aerosol device may be inserted into the cavity
simultaneously (i.e., as a combination). As seen in FIGS. 5 and 6, an
elongated tubular housing 31, having an open distal end 32 and a closed
proximal end 33 is provided with an aerosol delivery tube or wand 34,
preferably made from a rigid but flexible thermoplastic material, having a
lubricated nylon glider 35 at the distal end 32 thereof. Glider 35
facilitates entry of the flexible aerosol delivery tube or wand 34 into
the selected body cavity or into toroid 1 and eases passage centrally
therethrough. Housing 31 is provided with plastic guides 36 which ensure
the aerosol delivery tube 34 remains centred in housing 31. A slider 37 is
provided adjacent proximal end 33 and an aerosol/gas chamber 41,
containing an aerosolized drug, to facilitate sliding tube 34 out of
distal end 32 of housing 31, as seen in FIG. 7. Slider 37 slides in a
groove 38 in housing 31. As tube 34 advances from end 32, a spring 39 is
compressed between guide 36 and aerosol release valve 40. When tube 34 is
fully advanced, as seen in FIG. 7, a spring-loaded release valve button 42
is pushed radially outwardly through an appropriately located opening 43
in housing 31, as seen in FIG. 7. Upon depressing button 42, valve 40
opens and starts to release the aerosolized drug contained in chamber 41
through the tip 35 of tube 34. At the same time, button 42 is again
internalized within housing 31 and is moved towards proximal end 33
thereof as compressed spring 39 extends, as seen in FIG. 8. It will be
appreciated that the aerosolized drug is ejected directly onto the walls
of the urethra or other body cavity as the end 35 is withdrawn, thereby
painting the drug in a relatively uniform manner onto the walls, for
direct assimilation without any physical contact with the withdrawing tube
34 and/or toroid 1. Preferably the drug is in the form of a base compound
or salt and more preferably without a solid or liquid carrier. Solid | | |
