Note: Descriptions are shown in the official language in which they were submitted.
CA 02409039 2002-11-14
WO 01/87396 PCT/GB01/02221
DRUG DELTVERY MASK
Field of the Invention
The invention relates to the delivery of drugs to animals, and more
particularly to
devices for enabli.ng the delivery of drugs or medicaments to animals for
pulmonaty or nasal
absorption via the mouth and or nose.
Summary of the Related Art
In many circumstances, it is desired to deliver a drug or a rnedicarn.ent to
an animal,
and in particular a mammal, such as a human, a dog or a horse, for pulmonary
or nasal
absorprion. Direct application, such as by a spray or aerosol delivery device,
or a ciry powder
delivery device, is di.fficult due to movements of the animaL To enable such
application of
medicaments in the prior art, an elongated, generally cup-shaped "mask" is
often provided,
having a relatively large open base end for fitment over an animaPs nostril or
muzzle and
having a medicament adrninistration port opposite that base end. Typically the
mask is made
out of a semi-rigid material (eg, sheet polycarbonate) and is provided in
various sizes for use
with different sized animals.
In use in the prior art, an appropriate sized mask is selected, and the open
base end is
positioned over the animal's nosuil or muzzle, preferably with a-friction fit
at the open base
end. The size of the open end is such that at least a rough seal is
escablished between the
open end of the mask and the animal's nosrxil or muzzle. When t}ae mask is so
positioned,
mtedicainent is delivered at the medicament administrative port, for example
by spzay; aerosol
delivery device, or dry powder m.edicament delivery device, either
breathraccivated or user-
driven. As the animal breathes, the xn.edicament is drawn in-.o one (or borh)
nostril(s), or in
the mouth and into the lungs or the nasal passages.
This mask-type administration of inedicarnents lias proven to be a generally
effective
method for medicament delivery. I-iowever, there are inconveniences and
difficulties
CA 02409039 2002-11-14
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associated with the prior art masks. More particularly, because of the semi-
rigid structure of
such masks, the masks are bulky and take up significant volume when carried
around by a
veterinarian, or other provider. Moreover, the'semi-rigid structure of su.ch
masks makes it
necessaiy to provide a set of various sized inasks in order to be able to
provide masks for
correspondingly sized animals. In addition, because of the "rough" nature of
the seal
provided by the semi-rigid material of the conventional masks, many of those
masks are
provided with tubes, and the like, for insertion deep into the animal's
nosuxls. The latter type
of mask is pardcularly diffieult to clean making it difficult to use it for
more than one anirnal
at a time without cross-contamination.
Therefore, there is a need for an improved mask for delivering drugs to
ariianals for
pulmonary or nasal absorption via the mouth andlor nose. Such improved mask
should be
(a) collapsible to a relatively small volume form for ease and convenience in
transport; (b)
adaptable for use with different sized animals; and (c) easily cleaned, to
pemut re-use with the
same or different animals.
$RIEP SUMMARY OF THE INVENTIoN
The present invention is a drug or medicarnent, delivery device for fitment to
the
approprim portion of the head of the animal such as the front of the head or
over one nostil
for the effective delivery of drugs or medicaments, for pulmonary or nasal
a6sorption. The
device is in the form of a mask. The mask is collapsible to permit use in a
full or parrially
open state, and to permit easy and convenient transport in a collapsed or
closed scate. In a
preferred form, the mask of the invention is pardcuIarly adaptable to
accommodate size
variation in animals,
The drug delivery mask of the invention is adapted for removable fixture to
the
appropriate portion of the head of the animal such as the front of the head
(i.e, a portion of
the face), the nostril or the muzzle. The mask includes two or more
telescopable sections,
which are coupled together. Each section includes a relatively inflexible ring
defining an
associated first contour, and each has a relatively flexible skirt extending
from its ring to a
distal edge. The distal edge of the'skirt defines an associated second
contour. The rings of
the inask are nestable, forming a succession of monotonically decreasing sized
rings from a
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WO 01/87396 PCT/GB01/02221
largest ring to a smallest ring. Preferably, each ring fits inside the next
larger ring in the
succession, although in some forms two adjacent rings in the succession may be
same size,
and may not nest with each other. The second contour of a skirt of each ring
in the
successxon, is substantially the same as, and is joined to, the first contour
of the next ring of
the succession. The various joined sections may be formed (such as by
rnolding) as a unitary
struccure.
The present invention is intended for use with any animal which may experience
the
benefits of the invention. roremost among such animals are those which are
diffzcult to
control or cannot be rnade to cooperate ui the delivery of drugs or
xnedicaments via
conventional delivery devices. Hence the term "animal" is used to designate
patients such as
infants, children, physically or mentally disabled patients, as well as any
other animal (e.g,, a
dog, a cat or a horse).
An airborne medicament interface adapter extends from the skirt of the
smal.lest ring.
The medicament interface adapter is adapted to couple that skirt to a
medicament dispenser.
Preferably, the medicament dispension is breath-activated but may be user
(e.g., care giver)
actuated. The rnedicament dispenser may be in the form of a dry powder
medicament
dispenser, or in aerosol dispenser. Alternatively, a user-actuated spray
dispenser may be used.
The mask also includes an animal interface adapter extending from the largest
ring.
The animal interface adapter is adapted to provide a substantial (although not
necessarily
complete) pneumatic seal becween the animal interface adapter and the
appropriate portion of
the head of the animal (e.g., the front of the head of a small child, the
nostril or the muzzle of
any animal sucli as cats, dogs or horses). By way of example, the animal
interface adapter may
be in the form of a thin or tapered flexible sheet, which when pressed against
the area around
the appropriate portion of the head, forms at least a rough seal. As a furrher
example, the
animal interface adapter may be in the form of a stretchable, nonunally conic-
frnutnun shaped
elastic sheet, extending from the largest ring. Irx the elastic form, the
sheet may be stretched
as the largest rxng is moved over the nostril or muzzle of the animal. In some
fomns, an elastic
or otherwise adjustable strap e.tends from the animal interface adapter, where
the strap may
be placed around the back of an animal's head to secure the mask in place.
3
CA 02409039 2006-07-24
In a preferred form of the inventions, the sections of the mask are formed by
molding as a unitary structure, made from one of the group consisting of a
thermoplastic
elastomer, high density polyethylene, low density polyethylene, polypropylene
and
silicone rubber. One of skill will appreciate that any material or method
available in the
art can be utilized in carrying out the invention. However, preferred
materials methods
are described. Materials, reagents and the like to which reference is made in
the
following description and examples are obtainable from commercial sources,
unless
otherwise noted.
The rings may be circular, elliptical or some other closed shape. By way of
example, the respective rings may have a C-shaped cross-section, to impart a
relatively
inflexible characteristic, with its associated skirt extending from one end of
the C and the
distal edge of the skirt from the next being joined to the other end of the C.
The skirts
may be a material to impart a relatively flexible characteristic. Various
dimensions and
geometries may be used in keeping with the invention.
In accordance with one aspect of the present invention there is provided a
drug
delivery device for removable fixture to an animal, comprising:
a) an airborne medicament interface adapter adapted to couple to a medicament
dispenser in a sealed manner;
b) an animal interface adapter adapted to establish a substantial seal between
the
animal interface adapter and the animal; and
c) a relatively flexible sleeve extending along an axis between the medicament
interface adapter and the animal interface adapter, and having a cross
sectional
monotonically increasing between the medicament interface adapter and the
animal
interface adapter, wherein the relatively flexible sleeve comprises at least
two sections
extending along the axis, each of the sections including a relatively
inflexible ring
defining an associated first contour, and a relatively flexible skirt
extending from the ring
to a distal edge defining an associated second contour, wherein the rings are
nestable,
forming a succession of monotonically decreasing sized rings from a largest
ring to a
smallest ring, and wherein the second contour of the skirt of each ring in the
succession,
4
CA 02409039 2006-07-24
is substantially the same as, and is joined to, the first contour of the next
smaller ring in
the succession; wherein the medicament interface adapter extends from the
distal edge of
the skirt of smallest ring; and wherein the animal interface adapter extends
from the
largest ring.
In another aspect of the present invention there is provided A drug delivery
device
for removable fixture to an animal, comprising:
a) a relatively flexible sleeve extending along an axis between a proximal end
and
a distal end, and having a cross section increasing between the proximal end
and the
distal end, wherein the sleeve comprises at least two sections extending along
the axis,
each of the sections including a relatively inflexible ring defining an
associated first
contour, and a relatively flexible skirt extending in a monotonically
decreasing manner
from the ring to a distal edge defining an associated second contour, forming
a succession
of decreasing sized rings from a largest ring to a smallest ring, and wherein
the second
contour of the skirt of each ring in the succession, is substantially the same
as, and is
joined to, the first contour of the next smaller ring in the succession;
b) an airborne medicament interface adapter extending from the distal edge of
the
skirt of the smallest ring, wherein the medicament interface adapter is
adapted to couple
to a medicament dispenser in a sealed manner; and
c) an animal interface adapter extending from the largest ring, wherein the
animal
interface adapter is adapted to establish a substantial seal between the
animal interface
adapter and the animal.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature and the objects of the invention,
reference
should be made to the following detailed description and the accompanying
drawings in
which the reference numerals refer to like elements and in which:
Fig. 1 shows in exploded diagrammatic form, a drug delivery mask in accordance
with the invention;
4a
CA 02409039 2006-07-24
Fig. 2A shows in diagrammatic form, an exemplary drug delivery mask of the
invention, in an open state as it might be deployed over the head of an
animal;
Fig. 2B shows a sectional view of the mask of Fig. 2A along the lines 2A-2A;
Fig. 2C shows an enlarged sectional view of a portion of the mask contained in
the circle 2C of Fig. 2B;
Fig. 3A shows in diagrammatic form, the mask of Fig. 2, in a small volume,
closed or collapsed, form, as it might be configured for storage or transport;
Fig. 3B shows a section view of the mask of Fig. 3A along the lines 3A-3A;
4b
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WO 01/87396 PCT/GB01/02221
Fig. 3C shows a section view, sirnilar to Fig. 3B, of a portion of another
drug delivery
mask in accordance with the invention;
Fig. 4A shows a mask of the invention positioned over the nostril of an
animal;
Fig. 4B shows a mask of the invention, positioned over the muzzle of an
animal;
Fi,g, 5 shows in diagrammatic form, an exemplary drug defivery mask of the
invention,
in an open state as it rr~ght be deployed over the head of a smaU. human
chiid;
Fig. 6 shows in diagrarnmatic form, an exemplary drug delivery mask of the
invention,
in an open scate as it xnight be deployed in collapsible form over the nose of
a s,naall human
child;
Fig. 7 shows in diagranunatic form, an exemplary drug delivery mask of the
invention,
in an open state as it might be deployed over the head of a human adult;.
Pig. 8A shows a perspective view of another drug delivery mask in accordance
with
the invention;
Fig. 8B shows an end plan view of the mask of Fig. 8A;
Fig. 8C shows a sectional view of the mask taken along line SC--8C of Fig. 8B;
Fig. 8D shows a side elevation view of the mask of Fig, 8A;
Fig. SE shows a sectional view of the mask taken along line 8E--8E of Fig. 8D;
Fig. 8P shows an enlarged seccional'view of a portion of the mask contained in
circle
8F of Pig. 8E;
Fig. 8G shows an enlarged sectional view, similar to Fig. 8F, of another mask;
Fig. 8H shows an enlarged sectional view, sinailar to Fig. 8F, of another
mask; and
Fig. 9 shows a seccional view of a fiuther drug delivery mask in accordance
with the
invention.
5
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WO 01/87396 PCT/GB01/02221
DESeR1PTXON Or. THE PREFERRED EMBODIMENTS
An exemplary drug delivery mask 110 embodying the present invention for use
with
dogs, horses, humans and other mammals is shown in diagrammatic form in Pig.1.
The mask
110 is shown in exploded form to illustrate the various components which in a
fully formed
mask are a unitary structu.re.
A similar mask 110 is shown in Figs. ZA, 2B, 3A and 3B. The Mask 110 is a
unitary
structure. Figs. ?A and 2B show the mask 110 in an open state, having a bell
or similar shape,
as it mi.ght be deployed over the nostril or muzzle of an animal in use. rigs.
3A. and 3B show
mask 110 in a small volume, dosed, or collapsed, state, as it xnight be
configured to permit
convenient tran.sporc or storage.
As shown in exploded form in Fig.1 and in a unitary form in. Figs. 2A, 2B, 3A
and 3B,
the mask 110 indudes a sleeve 10 extending along a central axis "A" between an
airborne
medicament interface 20 and an animal interface adapter 30.
The sleeve 10 includes four sections 12, 14, 16, and 18 extending along the
central axis
"A". Each of the sections indudes a relatively inflexible ring Ri defining an
associated firsc
contour, having a relatively flexible skirt Si e.~ending therefrom to a distal
edge DEi. The
distal edge DEi defines a second contour, where "i" -1, 2, 3, .... The rings
R1;1Z2, R3, R4 of
assemblies 12, 14, 16, and 18 form a monotonically decreasing succession of
circular rings,
from the largest ring Ri to the scnallest ring R4. The succession is monotonic
in that the
individual rings in the succession are successively smaller, although in other
embodiments, a
ring may be the same (but not larger than) its nm (in the succession)
neighbor. Moreover, as
shown, each ring in the illustrated embodiment is sufficiently larger than the
next ring (in the
succession) so that the smaller ring fits within, i.e., nests, with its
neighbor. The distal edge
DEi of each ring Ri is the same size as the contour defined by next smaller
ring R in the
succession; that is, DE1 is the same size as R2, DE2 is the same size as R3
and DE3 is the
same size as R4. The distal edge of each skirt of sections 12, 14, and 16 is
joined to the ring of
the respective one of neighboring sections 14, 16, and 18.
In general, the mask is made from a soffr, supple material having good memory.
By
way of example, the rings and skins are made from plastics, for example, one
of the group
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WO 01/87396 PCT/GB01/02221
consisting of thermoplastic elastomers, high density polyethylene, low density
polyethylene,
polypropylene, and silicone rubber. By way of example, the thermoplastic may
be of the type
sold under the trademarks Elastolene, Evoprene, Pebax or Santoprene. With such
materials,
the mask 110 is easilywashable for use with a number of animals in kennels or
stables, with
no risk of cross-conrnamination. It is also envisioned that the mask can be
made from
materials other than plastic, such as a rubber, synrhetic rubber, silicone,
soft nylons, or can
include support materials, such as fibers or a cloth material, such as canvas,
contained within
the plastic or rubber to provided strength and durability.
In a preferred form, the mask 110 is a unitary scructure formed by molding for
example, high density polyethylene. In the illustrated embodiment, the
thickness of the
material forming mask 110 is in the range 0.12-0.15 cm, although other
thickitesses may be
used depending on the desired fleidbility. The rings are circular and are
relatively inflexiible.
As shown best in Fig. 2C, the rings are C-shaped in cross-section having an
outer diameter
0.5cm. The skirt for a ring extends from one end of the C and the distal edge
of the skirt of
the nexc larger ring is coupled to the other end of the C, C+ther forms of
rings may be used,
for example, solid rings having a circular or eUipitcal or other shaped cross-
section. The skirts
are relatively flexible. The adjacent ones of sections 12, 14, 16 and 1 S, are
joined together
DE1-to-n DE2-to-R3, and DE3-to-R4. Preferably, the entire structure 110, is
formed in a
single step with a molding process. The molding process may comprise
rotational molding,
blow molding or injection molding, for exaenple, The mask 110 can
alternatively be made by
vacuum forming. Many acceptable methods of forming the mask.110 can be used.
The airborne medicament interface 20, which is generally cylirtdrical, extends
from the
distal end DE4 of skirt S4 of section 14. The interface 20 may be formed from
the same
material as the skirt S4 or another compatible material. Preferably, the
interface 20 is integral
with, and merely an extension of the skirt S4. The end 20A of interface 20
opposite to the
end joined to skirt S4 is shaped to couple to, or receive, an excernal
aerosolizing medicament
dispenser 25. As shown in Fig. 1, the dispenser 25 is schematically
represented as an aerosol
dispenser, with its effluent plume directed to the interior of interface 20.
In various
embodiments, the dispenser 25 may be a metered dose breath-actuated or user-
(e.g,
veterinarian) operated inhaler and may be a dry powder or aerosol dispenser.
Preferably, the
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WO 01/87396 PCT/GBO1/02221
device 25 includes an output structure which directs airbome medicaments to
the interior of
mask 110.
The animal interface adapter 30 extends along a>as "A" from ring R1. In the
embodiments illustrated, the interface 30 is in the form of a tapered sheet
32. In other
errAbodiments, the sheet 32 can be in the form of a conic-frustrum shaped
shroud made of an
easily stretchable elastic material. The sheet 32 is adapted to provide a
stibstantial (although
not necessarily total) pneumatic seal between ring R1 and the nostril or
muzzle of an animal.
As illustrated in phantom in Fig. 1, the interface 30 may optionally include a
stretchable elastic
or otherwise adjustable strap 34 extending from or near opposite sides of r:ng
Ri, to permit
secure fixture of rnask 110 to the head of an animal.
With the configuration of mask 110'as shown, where the extension assemblies
12, 14,
16,18 and interfaces 20 and 30 form a unitaty strucrure, the mask 110 is
usable in two states; a
first or open state where the various sections 12, 14, 16, 18- are
"telescoped" out to form a
inask for fitment to an animal, and in a second or collapsed state to
establish a low volume
structure convenient for storage or transport. Figs. 2A and 2B illusrxate the
open state for
mask 110 and Figs. 3A and 3B illustrate the collapsed state for mask 110.
In addition, the mask 110 is also usable in an intermediate or parrially open
state,
wherein at leasc two of the various secrions are "telescoped" out to form a
mask for fitrnent to
an animal and where one of the rings forms the necessary seal to the aninnal.
In this way, a
single mask may accommodate several sizes of animals. Fig. 3C shows another
mask 111
according to the present invention, especially adapted for use in an
intermediate state. The
mask 111 of Fig. 3C is similar to the mask 110 of Pigs. 1 through 3, such that
elements that
are the same have the same reference numerals. The skirts S1 and S3 of the
mask 111 of Fag.
3C, however, are provided with a greater length (along the axis "A"), such
that when the mask
111 is in an intermediate or parrially open state the folded skirt S2 e.nends
beyond the animal
interface 30.
Fig. 4A shows an anim.a 40 (horse) wirh the mask 110 positioned over one of
its
nostrils. Fig. 4B shows an animal 40 (dog) with the mask positioned over the
muzzle of the
animal. When appIied to large animals, in particular to horses, the mask is
preferably
8
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WO 01/87396 PCT/GB01/02221
positioned over one nostriI only. It has been found in practice, that a horse
has suffcient
vacuum in one nostril when it breathes in (without havkg to block up the
oth,er nostril) to
effect the suitable medicament flow froczi delivery device 25.
The device 25 may be used for any drug formuladon which may be advantVageously
administered to the lung or nasal passages in an animal, to cure or alleviate
any illness or its
symptoms- Tqpical illnesses indude COPD, aschma, allergy, etc.. , and suitable
drugs indude
A-agonists or antagoniscs, steroids eg, bedomethasone, #luticasone or
budesonide, anti-
cholinergics eg., ipratropium brotnide, etc:.. . Therapeutirally effective
formulations and
dosages to be adrniniscered using the devices described herein are well known
to pr-actitioners.
One of skiIl win appreciate that pracationers may opt to alter dosages and/or
formulations.to
fit a particular patient/animal needs.
An exemplary drug delivery mask 110 showing the use of the invention for
humans
50, is shown in diagrammatic form in Figs. 5 and 6. The mask of Fig. 5 indudes
all the
charaaeristics described above but is especially adapted for human use.
The mask 110 is a unitarysrrucnue. Fig. 5 shows the mask 110 in an open staze,
having a bell or similar shape, as it might be deployed over the nostrils and
mouth of a small
chnd 50 in use. In various embodiments, the dispenser 25 may be a metered dose
breath-
actuated or user-(e.g., care giver) operated inhaler and may be a dry powder
or aerosol
dispenser. In other embodiments, the sheet 32 can be in the form of a conio-
frustum shaped
shroud made of an easily stretchable elastic material and/or highly flexible
material. The sheet
32 is adapted to provide a substantial (although not necessarily total)
pneuanatic seal between
ring Ri and the nostrils and/or mouth of a human 40. As illustrated in phaatom
in Figs. 5
and 6, the interface 30 may optionally include a stretchable elastic or
otherwise adjustable
strap 34 extending from or near opposite sides of ring Ri, to permit secure
fixture of mask
110 to the front of the face (mouth and/or nostri7s) of a human 40. The mask
may fit over
either the nostrils or the mouth separately. It should be understood, however,
that the mask
110 can be used without the scrap 34 or with a different type of strap(s).
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Fig. 6 illustrates the mask 110 used in a parcially open form, where one of
the rings R1
forms the necessary seal around the nose of a human 50. In this way, a single
mask 110 may
accomtnodate various sizes of the front of the face (mouth and/or nostrils) of
a human 40.
Fig. 7 shows a human 50 (human adult or elderly person) with the mask 110
positioned over the nostrils and mouth of the human 50. The mask 110 in this
figure mary
also fit over either the nostrils or the mouth separately. The device 25 may
be used for any
drug fornnulation that may be advantageously adrninistered to the lung or
nasal passages in a
human 50 or 40, to cure or alleviate any illness or its symptoms. Typical
illnesses include
COPD, asthma, allergy, etc.. , and suitable drugs include (i-agonists or
antagonists, steroids e.g,,
beclomethasone, fluticasone or budesonide, anti-cholinergics e.g., ipratropium
bromide, etc..
The doses for childresi may be the same or similar to those used to treat
adult diseases or may
be increased or decreased or given in multiple applications as dependant on
the size of the
hunaan.
Figs. 8A-8E show an additional mask 210 according to the present invention.
The
mask 210 is similar to the mask 110 of Pigs.1 through 3, such that elements
that are the same
have the same reference numerals. As also shown in Fig. 8F, the rings R1, R2,
R3, and R4 of
the mask 210 each have a four-sided cross-section transverse to the axis "A"
instead of a C-
shaped cross-section. The cross-seccion of the ring R3 of Fig. 8F is a
trapazoid that extends
transversed to the a~ris "A". The rings Ri can each have alternative cross-
sections including a
rectangular cross-section that extends transversed to the axis "A" as shown in
Fig. 8G, or a
reccangvlar cross-section that e,Ytends at anangle to the axis "A" as shown in
Fig. 81-L Many
variations of the ring Ri are possible under the scope of the present
invention.
Fig. 9 shows a funher mask 310 according to the present invention. The mask
310 is
similar to the mask 110 of Figs.1 through 3, such that elements that are the
same have the
same reference numerals. The sleeve 10 of the mask 310, however, does not
indude the
different multiple rings and skirts of the mask 110 of Figs.1 through 3. The
mask 310 is, in
effect, a more simple embodiment of the present invention, and indudes the
airborne
medicament interface adapter 20, the mammal interface adapter 30, and the
relatively flexible
sleeve enending along the axis "A" between the medicament interface adapter
and the
CA 02409039 2002-11-14
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mammal interface adapter. The sleeve 10 has a cross sectional monotonically
increasing
between the medicament interface adapter and the mammal interface adapter.
Examnle I
---,~
Pediatnic Use of the Drug DelxverX Mask
To illustrate the effectiveness of a representative embodiment of the
invention, the
device shown in Fig. 2 is used to administer various medications to a group of
human patients
between the age of 0-17. In the case of medications requiring pulmonary or
nasal absorption,
the mask is held in place over the nostrils and/or the mouth and against the
face of the patient
being treated. In the case of medications specihcally requiring nasal
absorption the mask is
placed over both nostrils (see Figure 6). In the case ofpulmonary medicaments,
blood plasma
analysis will reveal concentrations levels of the administered medications
consistent with
pulmonary absorption. In the case of medicaments which are nasally absorbed,.
effective
delivery will be confirmed by observing an ascertainable improvement in the
patients
symptoms.
Equivalents
While the claimed invention has been described in detaii and with reference to
specific
embodiments thereof, it will be apparent to one of ordinary skill in the act
that various
changes and modifications can be made to the clauxzed invention without
departing from the
spirit and scope thereof. Thus, for example those skilted in the azt will
recognize, or be able
to ascertain, using no more than routine experixnernation, numerous
equivalents to the
specific substances and procedtu-es described herein. Such equivalents are
considered to be
'arithin the scope of this invention, and are covered by the following claims.
11
