U.S. patent application number 11/542554 was filed with the patent office on 2007-04-05 for compositions and methods for improved skin care.
Invention is credited to Mark A. Pinsky.
Application Number | 20070077292 11/542554 |
Document ID | / |
Family ID | 37906509 |
Filed Date | 2007-04-05 |
United States Patent
Application |
20070077292 |
Kind Code |
A1 |
Pinsky; Mark A. |
April 5, 2007 |
Compositions and methods for improved skin care
Abstract
Compositions and methods for administering collagen to a human
subject have been developed. The collagen-containing lipid vesicles
of the invention provide a delivery system for human collagen which
eliminates problems associated with chemical and physical
instability of the collagen as well as immune responses to
non-human collagen.
Inventors: |
Pinsky; Mark A.; (West Palm
Beach, FL) |
Correspondence
Address: |
SALIWANCHIK LLOYD & SALIWANCHIK;A PROFESSIONAL ASSOCIATION
PO BOX 142950
GAINESVILLE
FL
32614-2950
US
|
Family ID: |
37906509 |
Appl. No.: |
11/542554 |
Filed: |
October 3, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60723043 |
Oct 3, 2005 |
|
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60833045 |
Jul 25, 2006 |
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Current U.S.
Class: |
424/450 ; 424/59;
424/70.13; 424/70.14; 514/17.2; 514/18.3; 514/18.7; 514/18.8;
514/3.3; 514/54 |
Current CPC
Class: |
A61K 8/735 20130101;
A61K 8/65 20130101; A61Q 19/02 20130101; A61K 9/127 20130101; A61K
47/42 20130101; A61P 17/16 20180101; A61P 15/18 20180101; A61K
9/0014 20130101; A61K 38/39 20130101; A61Q 19/04 20130101; A61K
8/14 20130101; A61Q 19/08 20130101; A61K 9/1272 20130101; A61K
31/728 20130101; A61P 17/00 20180101; A61K 47/36 20130101; A61Q
19/00 20130101; A61K 38/39 20130101; A61K 2300/00 20130101 |
Class at
Publication: |
424/450 ;
514/012; 514/054; 424/059; 424/070.13; 424/070.14 |
International
Class: |
A61K 38/39 20060101
A61K038/39; A61K 31/728 20060101 A61K031/728; A61K 8/73 20060101
A61K008/73; A61K 8/64 20060101 A61K008/64; A61K 9/127 20060101
A61K009/127 |
Claims
1. A liposome comprising at least one component selected from the
group consisting of hyaluronic acid and collagen.
2. The liposome, according to claim 1, comprising hyaluronic
acid.
3. The liposome, according to claim 2, wherein the hyaluronic acid
is cross-linked.
4. The liposome, according to claim 2, wherein the hyaluronic acid
is not cross-linked.
5. The liposome, according to claim 1, wherein the hyaluronic acid
is linear hyaluronic acid of less than 500 kDa.
6. The liposome, according to claim 1, comprising collagen.
7. The liposome, according to claim 6, wherein the collagen is
human collagen.
8. The liposome, according to claim 6, wherein the collagen is a
recombinant collagen.
9. The liposome, according to claim 6, wherein said collagen is a
collagen derivative.
10. The liposome, according to claim 6, wherein said collagen is a
Type I or Type III collagen.
11. The liposome, according to claim 6, wherein said collagen is in
a particle size of less than 800 nm.
12. The liposome, according to claim 6, wherein said collagen is in
the fibril form.
13. The liposome, according to claim 1, which comprises collagen
and hyaluronic acid.
14. The liposome, according to claim 1, further comprising at least
one of the group consisting of desquamation agents, anti-acne
agents, anti-wrinkle agents, vitamin B.sub.3 compounds, retinoids,
hydroxyl acids, anti-oxidants, radical scavengers, chelators,
flavonoids, anti-inflammatory agents, anti-cellulite agents,
topical anesthetics, tanning agents, skin lightening agents, skin
soothing and skin healing agents, antimicrobial and antifungal
agents, sunscreen agents, conditioning agents, structuring agents,
thickening agent, and preservatives.
15. The liposome, according to claim 1, which is paucilamellar.
16. The liposome, according to claim 1, which comprises
non-phospholipid surfactants.
17. A composition for delivering an agent into the skin of a
subject wherein said composition comprises a cyclodextrin having
associated therewith the agent, wherein the agent is selected from
the group consisting of collagen and hyaluronic acid.
18. A method for administering an agent into the skin of a subject,
the method comprising the step of contacting the skin of the
subject with a composition comprising a carrier comprising a cavity
having encapsulated therein an agent selected from the group
consisting of collagen and hyaluronic acid, wherein said carrier is
a liposome or a cyclodextrin.
19. The method, according to claim 18, wherein said carrier is a
liposome.
20. The method, according to claim 19, wherein the liposome
comprises hyaluronic acid.
21. The method, according to claim 19, wherein the liposome
comprises collagen.
22. The method, according to claim 19, wherein the liposome further
comprises at least one of the group consisting of desquamation
agents, anti-acne agents, anti-wrinkle agents, vitamin B.sub.3
compounds, retinoids, hydroxyl acids, anti-oxidants, radical
scavengers, chelators, flavonoids, anti-inflammatory agents,
anti-cellulite agents, topical anesthetics, tanning agents, skin
lightening agents, skin soothing and skin healing agents,
antimicrobial and antifungal agents, sunscreen agents, conditioning
agents, structuring agents, thickening agent, and
preservatives.
23. The method, according to claim 19, wherein the liposome is
paucilamellar.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit of provisional patent
applications Ser. No. 60/723,043, filed Oct. 3, 2005; and Ser. No.
60/833,045, filed Jul. 25, 2006, which are hereby incorporated by
reference in its entirety, including any figures, tables, or
drawings.
BACKGROUND OF THE INVENTION
[0002] The skin is the largest organ in the human body and consists
essentially of two primary layers--the epidermis and the dermis.
The epidermis is the outermost layer and, among other things,
controls water loss from cells and tissue. The dermis is the layer
below the epidermis and contains blood vessels, lymph vessels, hair
follicles and sweat glands. Below the dermis is the hypodermis.
Although the hypodermis is considered to be part of the
integumentary system, it is not generally considered to be a layer
of the skin. The hypodermis is used mainly for fat storage.
[0003] The outermost epidermis is made up of stratified squamous
epithelium with an underlying basement membrane. It contains no
blood vessels, and is nourished by diffusion from the dermis. The
main type of cells that make up the epidermis are keratinocytes,
with melanocytes and Langerhans cells also present. The epidermis
can be further subdivided into the following strata (beginning with
the outermost layer): corneum, lucidum, granulosum, spinosum,
basale. Cells are formed through mitosis at the innermost layers.
They move up the strata changing shape and composition as they
differentiate and become filled with keratin. They eventually reach
the corneum and become sloughed off. This process is called
keratinization and takes place within about 30 days.
[0004] The dermis consists largely of the protein collagen, which
forms a network of cross-linked fibers providing a framework for
blood vessels and cell growth. Because it is the primary component
of the dermis, collagen acts as the support structure for the skin.
The health and stability of collagen is a critical factor in
determining the contour, wrinkles and lines in the skin.
[0005] Hyaluronic acid (HA) is a natural substance found in all
living organisms in soft connective tissues, the vitreous humor of
the eye, some cartilage and joint fluids, and skin tissue. In skin
tissue, hyaluronic acid is a jelly like substance that fills the
space between collagen and elastin fibers. Its role is to provide a
mechanism of transport of essential nutrients from the bloodstream
to living skin cells, to hydrate the skin by holding in water, and
to act as a cushioning and lubricating agent against mechanical and
chemical damage. Over time however, due to aging and other external
factors, the body's natural supply of hyaluronic acid is slowly
absorbed and disappears gradually.
[0006] There are 7 to 8 grams of hyaluronic acid in adults, 50% of
which (3.5-4.0 g) are found in the skin. It is distributed at
approximately 0.5 mg/g in the dermis and about 0.1 mg/g in the
epidermis. It is not specific to species or organs and is thought
to be without risk of promoting allergy or causing a foreign body
reaction.
[0007] Administration of hyaluronic acid can be used to help
hydrate the skin, smooth wrinkles, and generally improve skin
appearance. The effectiveness of such administration is limited by
the relatively rapid breakdown of this compound caused by enzymes
that exist naturally in the body. In recent years, efforts have
been made to create longer lasting hyaluronic acid compositions.
Specifically, cross-linked hyaluronic acid compounds have now been
developed that significantly increase the half-life of HA in the
body. These compositions, which have reduced water solubility, are
injected for cosmetic treatment. These injections are similar to
collagen injections and, apart from being non-allergenic, have the
same limitations and drawbacks. These limitations and drawbacks are
discussed in more detail below.
[0008] Collagen, a naturally occurring fibrous protein found in
both humans and animals, provides structural support for bones,
tendons, ligaments, and blood vessels, in addition to its role in
the skin. Collagen is the most abundant protein in the body.
[0009] There are several major types of collagen, which give rise
to the variety of structural and functional properties that
collagen exhibits throughout the body. With age or injury, the
collagen in a person begins to weaken and lose its elasticity. In
the skin, this process eventually results in the appearance of
wrinkles.
[0010] The basic structural unit of a collagen fiber is
tropocollagen. It consists of a triple helix of three intertwined
peptide chains of approximately 1000 amino acid residues. The basic
polypeptide unit of the peptide chain is a repeating sequence of 3
amino acids, where every third residue is a glycine, and the other
two alternate between proline and hydroproline. It is important to
the stabilizing feature of the collagen fiber that the glycine
residue is every third residue because its small side chain allows
for tight coiling of the three helices, providing a strong
stabilizing structure.
[0011] In young skin, the collagen remains intact and elastic,
however, as the skin ages, the support structure weakens, the skin
loses elasticity and the collagen support wears down from the
cumulative stress of, for example, facial expressions. This causes
lines and wrinkles to appear in the skin.
[0012] Collagen replacement therapy can be used to treat conditions
associated with the breakdown or loss of collagen. For example,
skin wrinkles can be treated by injecting highly purified collagen
into the dermis. Injection of collagen has also been used to soften
scar tissue and create fuller lips.
[0013] Current collagen replacement therapies include collagen
injections in which purified animal collagen is used to replace
lost tissue. Zyderm.RTM. and Zyplast.RTM. are bovine collagen
implants that are injected into the dermis. There they become
incorporated into the human collagen framework and replenish the
skin's natural collagen thereby restoring the support structure and
the contour of the skin. This injection therapy enhances and
improves the natural appearance of skin and smoothes facial lines
and scars.
[0014] Procedures involving injecting collagen are not without
risk. For example, bovine collagen injections can cause allergic
reactions such as redness, swelling, firmness, itching and, in rare
instances, abscess formation. Worse, some physicians have reported
the occurrence of connective tissue diseases such as rheumatoid
arthritis, systemic lupus erythematosus, dermatomyositis (DM), and
polymyositis (PM) subsequent to collagen injections in patients
with no previous history of these disorders.
[0015] Also, the injection process itself poses certain challenges.
For example, the practitioner injecting collagen (and/or hyaluronic
acid) must control the depth, orientation and position of the
needle at a particular injection site, while providing an inward
force on the plunger that is sufficient to force a controlled flow
rate of high viscosity collagen out of the needle and into the
exact location in the dermis that will provide the desired cosmetic
effect. The locating of the needle tip at the proper depth within
the dermis is also difficult for the practitioner. To engage the
tip of the needle at the proper injection depth, the practitioner
may move the needle inwardly and outwardly with respect to the
surface of the skin (epidermis). However, there is no visual
reference point, other than the end of the syringe body, from which
the practitioner can easily determine the extent that the needle
extends into the dermis. Thus, the needle tip may be placed too
deep, or too shallow, for the intended application. It should be
appreciated that the person (practitioner) injecting the collagen
must have good, steady control of the fingers, hand and arm and
also have excellent eye-hand coordination to be an effective
provider of cosmetic collagen injections. These qualities are not
always present in individuals, and this has limited the
availability of collagen therapy to patients.
[0016] In addition to injection, collagen may be delivered to the
skin by topical application. Unfortunately, such topical collagen
therapy has proven less than effective as conventional forms of
collagen do not appear to penetrate into the dermis. As noted
above, the skin consists of multiple layers and is extremely
complex in terms of its function as well as its chemical make-up.
Transdermal (through the skin) application of medicines and other
substances poses a wide range of formulation hurdles. The ability
to deliver desired substances to a layer within the skin is
equally, if not even more, difficult.
[0017] Various means for delivery of substances to or into the skin
have been proposed.
[0018] U.S. Pat. No. 5,354,564 discloses personal care products
comprising an aqueous dispersion of particles of silicone wherein
said particles have a surface modifier adsorbed on the surface
thereof in an amount sufficient to achieve a particle size of less
than about 400 nanometers (nm).
[0019] U.S. Pat. No. 5,660,839 discloses incorporating deformable
hollow particles into cosmetic and/or dermatological compositions
containing fatty substances, for markedly reduce or eliminate the
sticky and/or greasy feel attributed to these fatty substances.
[0020] U.S. Pat. No.5,667,800 discloses an aqueous suspension of
solid lipoid nanoparticles, comprising at least one lipid and
preferably also at least one emulsifier, for topical application to
the body.
[0021] U.S. Pat. No. 5,780,060 discloses microcapsules with a wall
of crosslinked plant polyphenols and compositions containing them.
The microcapsules are obtained by the interfacial crosslinking of
plant polyphenols, particularly flavonoids.
[0022] U.S. Pat. Nos. 5,851,517 and 5,945,095 disclose compositions
including a dispersion of polymer particles in a non-aqueous
medium. A dispersion of surface-stabilized polymer particles can be
used in a non-aqueous medium, in a cosmetic, hygiene or
pharmaceutical composition. The dispersions may, in particular, be
in the form of nano-particles of polymers in stable dispersion in a
non-aqueous medium.
[0023] U.S. Pat. Nos. 5,759,526 and 5,919,487 disclose
nanoparticles coated with a lamellar phase based on silicone
surfactant and compositions containing them. The nanoparticles, and
in particular nanocapsules, provided with a lamellar coating
obtained from a silicone surfactant, can be used in a composition,
in particular a topical composition, for treatment of the skin,
mucosae, nails, scalp and/or hair.
[0024] U.S. Pat. No. 5,188,837 discloses a microsuspension system
and method for its preparation. The microsuspension contains
lipospheres which are solid, water-insoluble microparticles that
have a layer of a phospholipid embedded on their surface. The core
of the liposphere is a solid substance to be delivered or a
substance to be delivered that is dispersed in an inert solid
vehicle such as a wax.
[0025] U.S. Pat. No. 4,919,841 discloses a process for preparing
encapsulated active particles by the steps of: dispersing active
materials in molten wax; emulsifying the active/wax dispersion in
an aqueous surfactant solution for no longer than 4 minutes;
quenching the capsules by cooling; and retrieving solidified
capsules. Examples of active materials are fragrances.
[0026] Each of these methods has disadvantages, particularly with
respect to the delivery of collagen and/or hyaluronic acid.
[0027] Liposomes are vesicular lipid membrane structures that
enclose, for example, a volume of water. The existence of liposomes
has been known for many years. In the early 1900's, researchers,
studying isolated lecithin (phosphatidylcholine), cephalin
(phosphatidylethanolamine/phosphatidylserine), phrenosin
(galactosyl ceramide) and kerasin (glucosyl ceramide), found that
all of these molecules would swell in water to form hydrated
multilamellar layers, consisting of lipid bilayers separated by
water. Also, mixtures of ionic and nonionic lipids dispersed in
water were found to form stable "emulsions" in which the lipid
molecules take up positions side by side to form a homogeneous
mixed phase. These emulsions were the equivalents of what are now
called multilamellar liposomes.
[0028] Physical and chemical studies have shown that amphiphiles
form certain preferred arrays in the presence of water. Formation
of these arrays, which include micelles, monolayers and bimolecular
layers, is driven by the need for the polar head groups, which may
be ionogenic or not, to associate with water and the need of the
apolar, hydrophobic tail to be excluded from water. Exactly which
type of structure is assumed depends upon the nature of the
amphiphile, its concentration, the presence of other amphiphiles,
temperature, and presence of salt and other solutes in the aqueous
phase.
[0029] Until recently, liposome technology has been concerned
mostly with vesicles composed of phospholipids, predominantly
phosphatidylcholine, and these continue to be the focus of most
publications and patents. However, although phospholipids are
suitable for certain pharmaceutical applications, phospholipid
liposome technology has been beset by serious problems, for
example, phospholipids turn over rapidly in vivo and are unstable
in storage. Also, they are labile and expensive to purify or
synthesize, and the manufacture of phospholipid liposomes is
difficult and costly to scale up.
[0030] Although liposomes are well known in the art, there are no
previous reports of their use to efficiently deliver collagen
and/or hyaluronic acid in a skin care formulation.
BRIEF SUMMARY OF THE INVENTION
[0031] The subject invention pertains to new and advantageous skin
care compositions. In a preferred embodiment, the subject invention
provides lipid vesicles (liposomes) incorporating hyaluronic acid.
Particularly preferred is the use of cross-linked hyaluronic acid.
Free, or non-crosslinked hyaluronic acid may also be used as a
component of the composition. In a further preferred embodiment,
the compositions of the subject invention also comprise vesicles
containing collagen. The compositions may also contain additional
skin care agents.
[0032] The subject invention further pertains to methods of using
such lipid vesicles for delivery of hyaluronic acid, collagen, and
other active ingredients to a patient to achieve enhanced skin
care.
[0033] Hyaluronic acid is a naturally occurring sugar that exists
in all living organisms and is a universal component of the
extra-cellular spaces of body tissues. It functions by holding
together collagen and elastin, thus providing a framework for the
skin. When applied to the skin according to the subject invention,
preferably in cross-linked gel form, hyaluronic acid acts as a
dermal filler by binding to water and providing volume to easily
fill in facial lines and cause visible plumping of the skin. When
used according to the subject invention hyaluronic acid acts as an
efficient hydrating agent.
[0034] In one embodiment, the present invention provides a skin
care composition with cross-linked hyaluronic acid that further
comprises a safe and effective amount of collagen, wherein the
formulation facilitates the active ingredients passing through the
epidermis and thus being released within the dermis of the skin. In
a further embodiment, the human collagen and/or crosslinked HA may
be delivered to the epidermis as well. Accordingly, the present
invention is useful in regulating and/or improving the condition of
the skin (including the appearance and/or feel of the skin) by
efficiently delivering hyaluronic acid and/or collagen to the
appropriate location within the skin.
[0035] In addition, the use of human collagen (e.g., recombinant
human collagen or human collagen isolated from human tissue or
cultured human fibroblasts), or a fragment thereof, is advantageous
for avoiding undesired side effects such as allergic or autoimmune
reactions. Advantageously, hyaluronic acid does not present a
significant risk of an allergic reaction.
[0036] The present invention also relates to methods of using such
compositions to regulate and/or improve the condition of skin. The
methods of the subject invention generally include the step of
topically applying the compositions to the skin (epidermis) of the
patient needing such treatment, wherein a therapeutically effective
amount of such composition is applied.
[0037] Advantageously, the present invention provides compositions
and methods for combating the aging of skin, wherein combating the
aging of skin can include, for example, hydration of the skin,
treating the appearance of wrinkles, fine lines, and other forms of
undesirable skin texture. By presenting collagen and/or hyaluronic
acid into the dermal and/or epidermal layer(s) of the skin, the
form, strength, as well as function of the skin is enhanced.
[0038] In certain embodiments, the compositions of the subject
invention comprise a dispersion of lipid vesicles that contain
agents, in addition to hyaluronic acid and collagen, that are
useful in delaying, minimizing, or eliminating skin aging,
wrinkling, and/or other histological changes typically associated
with the intrinsic conditions (such as aging, menopause, acne,
etc.) and extrinsic conditions (such as environmental pollution,
wind, heat, low humidity, harsh surfactants, etc.).
[0039] In an exemplary embodiment of the invention non-phospholipid
paucilamellar lipid vesicles incorporating human collagen and
hyaluronic acid are used to deliver collagen to the skin of a human
subject. Non-phospholipid paucilamellar lipid vesicles are
particularly advantageous for use in the invention as such vesicles
are stable and inexpensive to manufacture, and also feature a large
cavity size for holding collagen. In an alternative embodiment,
cyclodextrins are used to deliver the active agents to the dermis
layer of the skin.
DETAILED DESCRIPTION
[0040] The present invention is directed to materials and methods
for the topical administration of a therapeutically effective
amount of hyaluronic acid and/or collagen to a specific layer
within the skin in order to improve the condition of the skin.
Accordingly, in a preferred embodiment, the present invention
provides compositions, and methods for using such compositions,
comprising a dispersion of lipid vesicles that contain at least
hyaluronic acid and/or collagen (and, optionally, other skin care
agents), wherein the lipid vesicles facilitate penetration through
the epidermis and dispersal of the vesicle contents, into the
dermis layer of the skin.
[0041] Improvement of skin condition is often desired due to
conditions that may be induced or caused by factors internal and/or
external to the body. Examples include, but are not limited to,
environmental damage, smoking, radiation exposure (including
ultraviolet radiation), chronological aging, menopausal status
(e.g., post-menopausal changes in skin), stress, diseases, etc.
[0042] The present invention is useful for therapeutically and/or
prophylactically improving visible and/or tactile characteristics
in skin. For example, in one embodiment, the length, depth, and/or
other dimension of lines and/or wrinkles are decreased and
hydration is achieved.
[0043] "Improving skin condition" includes prophylactically
preventing or therapeutically treating a skin condition, and may
involve one or more of the following benefits: thickening of skin,
preventing loss of skin elasticity, and a reduction in lines or
winkles.
[0044] Following are additional definitions relevant to the subject
invention. It should be appreciated that the following definitions
are used throughout this application. Unless otherwise defined, all
technical terms used herein have the same meaning as commonly
understood by one or ordinary skill in the art to which this
invention belongs.
[0045] The term "epidermis" or "epidermal," as used herein, refers
to the outermost layer of the skin.
[0046] The term "topical application," as used herein, means to
apply or spread the compositions of the present invention onto the
surface of the epidermis tissue.
[0047] The term "dermatologically-acceptable," as used herein,
means that the compositions or components thereof so described are
suitable for use in contact with mammalian epidermal tissue without
undue toxicity, incompatibility, instability, allergic response,
and the like.
[0048] The term "therapeutically effective amount," as used herein,
refers to an amount of a compound (such as collagen) or composition
sufficient to induce a positive benefit, preferably a positive skin
appearance and/or feel. In accordance with the subject invention,
the therapeutically effective amount is an amount of collagen,
either alone or in combination with other agents, that regulates
and/or improves the skin, but where the amount is low enough to
avoid serious side effects, i.e., to provide a reasonable benefit
to risk ratio, within the scope of sound judgment of the skilled
artisan.
[0049] The term "sagging" as used herein means the laxity,
slackness, or the like condition of skin that occurs as a result of
loss of, damage to, alterations to, and/or abnormalities in dermal
structure and/or function.
[0050] The terms "smoothing" and "softening," as used herein, refer
to altering the surface of the epidermis tissue such that its
tactile feel is improved.
[0051] "Signs of skin aging" include, but are not limited to, all
outward visibly and tactilely perceptible manifestations as well as
any other macro or micro effects due to skin aging. Such signs may
be induced or caused by intrinsic factors or extrinsic factors,
e.g., chronological aging and/or environmental damage. These signs
may result from processes which include, but are not limited to,
the development of textural discontinuities such as wrinkles and
coarse deep wrinkles, skin lines, crevices, bumps, large pores
(e.g., associated with adnexal structures such as sweat gland
ducts, sebaceous glands, or hair follicles), or unevenness or
roughness, loss of skin elasticity, sagging (including puffiness in
the eye area and jowls), loss of skin firmness, loss of skin
tightness, loss of skin recoil from deformation, discoloration
(including undereye circles), blotching, sallowness, hyperpigmented
skin regions such as age spots and freckles, keratoses, abnormal
differentiation, hyperkeratinization, elastosis, collagen
breakdown, and other histological changes in the stratum corneum,
dermis, epidermis, the skin vascular system (e.g., telangiectasia
or spider vessels), and underlying tissues, especially those
proximate to the skin.
[0052] As used herein, "shear mixing" means the mixing of a
lipophilic phase with an aqueous phase under turbulent or shear
conditions that provide adequate mixing to hydrate the lipid and
form lipid vesicles
[0053] By the terms "disperse" and "dispersion" are meant
dissolution or forming a suspension or colloid to yield a flowable
phase.
[0054] As used herein, a "nucleic acid" or a "nucleic acid
molecule" means a chain of two or more nucleotides such as RNA
(ribonucleic acid) and DNA (deoxyribonucleic acid). A "recombinant"
nucleic acid molecule is one made by an artificial combination of
two otherwise separated segments of sequence, e.g., by chemical
synthesis or by the manipulation of isolated segments of nucleic
acids by genetic engineering techniques.
[0055] The terms "protein" and "polypeptide" are used synonymously
to mean any peptide-linked chain of amino acids, regardless of
length or post-translational modification, e.g., glycosylation or
phosphorylation. A "purified" polypeptide is one that has been
substantially separated or isolated away from other polypeptides in
a cell or organism in which the polypeptide naturally occurs (e.g.,
90, 95, 98, 99, 100% free of contaminants).
[0056] When referring to a nucleic acid or polypeptide, the term
"native" refers to a naturally-occurring nucleic acid or
polypeptide.
[0057] The compositions of the present invention, which enable
dermal layer dispersion of collagen, are useful for improving the
skin, including improving skin appearance and/or feel. For example,
compositions of the present invention are useful for improving the
appearance of skin condition by providing a visual improvement in
skin appearance following application of the composition to the
skin.
[0058] Advantageously, the compositions of the present invention
may have additional desirable properties, including stability, long
shelf-life, absence of significant skin irritation, and good
aesthetics. In certain embodiments, to accomplish such additional
benefits, the compositions of the invention further comprise
agents, in addition to the collagen, that promote composition
stability, reduce skin irritation, and/or enhance the aesthetic
appeal of the composition.
[0059] Examples of good aesthetics include compositions, such as
luxurious creams and lotions, that (i) are light and nongreasy,
(ii) have a smooth, silky feel upon the skin, (iii) spread easily,
and/or (iv) absorb quickly. Other examples of good aesthetics
include compositions that have a consumer acceptable appearance
(i.e. no unpleasant odor or discoloration present), and provide
good skin feel.
[0060] Although methods and materials similar or equivalent to
those described herein can be used in the practice or testing of
the present invention, suitable methods and materials are described
below. All publications, patent applications, patents, and other
references mentioned herein are incorporated by reference in their
entirety. In the case of conflict, the present specification,
including definitions, will control. In addition, the particular
embodiments discussed below are illustrative only and not intended
to be limiting.
Hyaluronic Acid
[0061] Hyaluronic acid (HA) is present throughout nature and is a
combination of repeated disaccharide units of glucuronic acid and
N-acetyl glucosamine. It is polyionic and has an axial hydrophobic
part and a central hydrophilic part. Hyaluronic acid is very
sensitive to hyaluronidases and, therefore, has a short half-life
in the body. In order to make it a wrinkle-filling product that has
sufficient sustainability over time it can be cross-linked.
[0062] Numerous substances can be used to cross-link hyaluronic
acid including formaldehyde, epoxides, polyaziridyl compounds,
divinyl sulfone and others. One cross-linking agent is divinyl
sulfone. This substance reacts readily with hyaluronic acid in
aqueous alkaline solutions, thereby providing cross-linked HA gels.
These gels swell in water. The swelling ratio depends upon the
degree of cross-linking of the gel. The degree of cross-linking can
be controlled by changing several factors including the molecular
weight of the HA, its concentration in the reaction mixture, the
alkali concentration and the polymer/DVS ratio. The swelling ratio
of these gels can be from 20 up to 8000, and more, depending upon
the reaction parameters.
[0063] An even more preferred cross-linking agent is 1,4-butanediol
diglycidyl ether (BDDE).
[0064] The swelling ratio of cross-linked HA gels is substantially
greater than the swelling ratio of cross-linked gels of other
polysaccharides obtained under the same reaction conditions. This
can probably be explained by the unique nature of HA (as compared
to other polysaccharides) and its water solutions. In water, a
large molecule of HA forms a very flexible, long random coil that
takes up a large volume in the solution.
[0065] The unique property of HA to give highly swollen
cross-linked gels can be used to effect modification of the
properties of cross-linked gels made of mixtures of HA with other
hydrophilic polymers. These polymers include other polysaccharides,
synthetic and natural, such as hydroxyethyl cellulose,
carboxymethyl cellulose, xanthan gum, glycosaminoglycans, proteins
and glyco proteins of various types, such as collagen, elastin,
albumin, globulin, etc, sulfated proteins, synthetic water-soluble
polymers, such as polyvinyl alcohol and its co-polymers,
co-polymers of poly-(hydroxyethyl) methacrylate and the like. Any
polymer soluble in water or aqueous alkaline solutions and
containing groups capable of reacting with DVS, namely, hydroxyl,
amino or sulfhydryl groups, can be used to obtain highly swollen
cross-linked mixed gels of HA.
[0066] Another convenient method of obtaining cross-linked
hyaluronic acid or mixed hyaluronic acid and other polymer gels
comprises treating dry polymer preparations, i.e., in the form of a
film with a cross-linking agent and subsequent swelling of the
product in the desired medium.
[0067] In one embodiment, linear HA of less than 500,000 Da can be
used.
[0068] As described herein, the administration of HA can be used to
advantageously improve the condition of the skin. Also, because of
its molecular structure, HA can be used to entrap and deliver
additional active agents (drugs). There are several methods for
combining a drug with the HA gel and, accordingly, several types of
products that can be obtained. One of the methods comprises
diffusing a drug into an HA gel when the gel is put into a solution
of the drug. The product obtained by this method is a gel in which
a drug substance is uniformly dispersed.
[0069] The same type of product can be obtained by dehydrating a
hyaluronic acid gel and reswelling it in a drug solution. To
dehydrate a gel one can use a water-miscible organic solvent or
alternatively, water from a gel can be removed by drying.
Preferable solvents are ethanol and isopropanol, and ketones such
as acetone, though other solvents can also be used.
[0070] Yet another method can be used to obtain products of this
type. This method comprises allowing a concentrated hyaluronic acid
gel resulting from a cross-linking reaction previously carried out
in a relatively concentrated solution of hyaluronic acid to swell
in a solution of a drug substance.
[0071] Although these three methods all result in products that are
essentially the same, each of the methods has certain advantages
when compared to any of the other methods for any specific product
and, hence, the choice of method should be made with consideration
given to such parameters as nature of the drug, the desired
concentration of the drug in the system, the delivery rate,
etc.
[0072] A drug delivery system of another type according to the
present invention is one in which a drug is covalently attached to
macromolecules of hyaluronic acid and/or other polymers forming a
gel. These systems are characterized by a substantially slower rate
of delivery than those described above. Delivery of a drug from
these systems occurs when the gel is degraded in the living body.
The degradation process is usually slower than diffusion. The rate
of the degradation process can be controlled by several means,
including adjusting the density of the cross-links in the gel or by
co-cross-linking hyaluronic acid with polymers which can be
degraded in the body more easily than hyaluronic acid, e.g.,
proteins. By changing the concentration of such polymer components
in the mixed gels, one can conveniently control their rate of
degradation and, thus, the rate of drug delivery.
[0073] Another possibility of drug delivery for this type of
product involves the use of such chemical bonds for attachment of a
drug to polymeric molecules forming a gel that has a controllable
rate of hydrolysis in a physiological environment.
[0074] To obtain this type of a product one can use a drug
substance that can react with a cross-linking agent. Yet another
method can be used to obtain this product. This method comprises
chemically modifying a cross-linked gel after its formation, using
the reactive hydroxyl groups of hyaluronic acid or the reactive
groups of the polymers co-cross-linked with the hyaluronic acid to
which a drug substance can be attached by numerous chemical
reactions. Alternatively, additional reactive groups can be
introduced by chemical treatment of a cross-linked gel which
affects the macromolecules of hyaluronic acid or co-cross-linked
polymers and a drug can be covalently attached to these newly
formed reactive groups.
[0075] The active agents can be cosmetic, dermatological, and
pharmaceutical active agents. Suitable active agents include, but
are not limited to, ceramides; vitamins; antioxidants; free radical
scavengers; moisturizing agents; anti-seborrhoeic agents; anti-UV
agents; keratolytic agents; anti-inflammatory agents;
melanoregulators; liporegulators; anti-ageing agents; antibacterial
agents; agents for combating hair loss; vascular protectors; anti
fungal agents; skin conditioners; immunomodulators; nutrients and
essential oils; retinoids; anesthetics; preservatives; antiseptics;
emollients; lubricants; humectants; pigments; dyes; hydroxy acids,
such as, alpha hydroxy acids, and beta hydroxy acids; elastin;
hydrolysates; epidermal growth factor; soybean saponins; and
mucopolysaccharides.
[0076] Several forms of hyaluronic acid have been developed by
cross-linking the acid with other natural acids or chemical
compounds to form gels that improve skin condition.
[0077] At present several commercial preparations are available.
These include Hylaform.RTM., extracted from coxcomb and marketed by
the Genzyme Company and Restylane.RTM. which is produced by
bacteria fermentation process using Streptococcus equi spices and
crosslinked with BDDE. These two compositions have the common
feature of being biphasic injectable substances, with particles of
hyaluronic acid cross-linked to a greater or lesser degree and
suspended in a more fluid or even non-cross-linked preparation.
[0078] Monophasic gel preparations of hyaluronic acid are contained
in other products such as Juvederm.RTM., Hydra Fille and
Esthelis.RTM.. As with the Restylane.RTM. each of these is produced
with BDDE, although the process is different resulting in the
monophasic gel.
[0079] In one embodiment, the crosslinked hyaluronic acid is
produced as a monophasic composition. After linearising the spine
of the native hyaluronic acid, cross-linking is started by adding
BDDE. Dynamic cross-linking allows a product to be obtained that
macroscopically has a homogeneous appearance, and microscopically
has a heterogenous appearance. This technique allows what is called
a Cohesive Polydensified Matrix to be obtained.
[0080] Placed in the presence of 1 ml of water for 2 minutes, the
gel remains cohesive, which is not the case for biphasic products
in which the "microparticle" component appears immediately. This
product is available under the tradename Esthe'lis.RTM..
[0081] The visco-elastic properties of Esthe'lis.RTM. make it a
substance that sculpts well in the tissue, with very gentle massage
to position it correctly. It does not leave an "implanted cord"
feeling and can even be referred to as having a lifting effect.
[0082] In a preferred embodiment of the subject invention,
hyaluronic acid is incorporated into lipid vesicles in order to
administer hyaluronic acid to the skin of a patient. As described
herein, any lipid vesicle suitable for encapsulating hyaluronic
acid and for administering to the skin of a human subject may be
used.
[0083] Advantageously, when used according to the subject
invention, this product can have a hydrating effect in the treated
area with, for example, abolition of crow's feet during treatment
of the eyes. The nasolabial folds are on the areas treated on the
cheeks.
Collagen
[0084] The compositions of the invention can include one or more
purified, or recombinant, collagens and/or collagen derivatives, or
a combination thereof. Collagen proteins useful in the invention
include any native collagen proteins obtained from animal (e.g.,
human) cells and tissue, recombinantly expressed human collagen
proteins (including fragments of the full-length collagen), and
combinations and/or formulations thereof.
[0085] Purified collagens for use in the methods and compositions
of the invention may be isolated from animal or human tissues;
however, the use of human collagen in the compositions and methods
of the invention is preferred when the subject to be treated is a
human in order to prevent an immune response to the collagen
material. Collagen that is extracted from its source material
(e.g., animal placenta, bone, hide, tendon) is typically a mixture
of collagen type I with some collagen type III. Collagen material
recovered from placenta, for example, is biased as to collagen type
and not entirely homogenous. Techniques for isolating collagen from
human placentas are described in U.S. Pat. Nos. 5,002,071 and
5,428,022.
[0086] In addition to employing collagen obtained directly from
natural sources, the methods and compositions of the invention
include many different types of collagen derivatives. Collagen
derivatives may vary from naturally-occurring collagens in several
respects. Collagen derivatives may be non-glycosylated or
glycosylated differently than naturally-occurring collagens.
Desired glycosylation patterns may be produced by a variety of
methods, including direct chemical modification and enzymatically
catalyzed glycosylation and deglycosylation reactions. Desired
glycosylation patterns may also be produced by inhibiting or
deleting enzymes necessary for producing the naturally-occurring
glycosylation patterns found on collagens.
[0087] Collagen derivatives also include various fragments of
naturally-occurring collagens. Such collagen fragments may be
produced by, among other methods, chemically or enzymatically
cleaving one or more peptide bonds. Collagen derivatives may also
contain one or more amino acid residue differences as compared with
corresponding amino acid residue positions in a naturally-occurring
collagen. Collagen derivatives containing such amino acid residue
substitutions may be produced by a variety of methods including
genetic engineering techniques and by in vitro peptide synthesis.
Additional collagen derivatives may be produced by varying the
amount of hydroxylysines and/or hydroxyprolines present in a given
molecule, by the varied expression of lysine hydroxylases, and/or
proline hydroxylases, wherein the hydroxylase genes (recombinant or
otherwise) are also expressed in a host cell for the expression of
recombinant collagen, or derivatives thereof.
[0088] In certain preferred embodiments of the subject invention,
pure recombinant collagen (e.g., types I or III) as opposed to the
various types found in animal (e.g., bovine) collagens can be used.
Pure forms of recombinant collagen have performance characteristics
that in some applications are preferred to those from animal
mixtures. A description of how to produce collagen types I-III by
recombinant DNA technology can be found, among other places, in
U.S. Pat. Nos. 5,405,757; 5,593,859; 6,617,431; 6,428,978;
PCT-published patent applications WO 93/07889 and WO94/16570, and
related patents and applications. The recombinant production
techniques described in these references may be readily adapted so
as to produce many different types of collagens, human or
otherwise. Because an immune response can be elicited against
non-human collagen material, human collagens produced by
recombinant DNA technology are preferably used in compositions and
methods of the subject invention.
[0089] A preferred collagen for use in the invention, for example,
is recombinant human collagen expressed in and purified from human
fibroblasts. This collagen material is produced by Inamed
Corporation (Santa Barbara, Calif.) and is sold under the trade
names CosmoDerm.RTM. and CosmoPlast.RTM.. Fibroblast cells used for
culturing collagen in this method are screened for known pathogens
and the resultant collagen material is tested for contaminants.
Once the collagen is isolated from the cells, it is subjected to
viral inactivation for increased safety. Methods for expressing
recombinant genes in human fibroblasts are well known in the
art.
[0090] Two additional collagen materials that are produced using
recombinant DNA technology and that can be used in the invention
are FG-5017 and FG-5016 (FibroGen, South San Francisco, Calif.).
FG-5017 is made of recombinant human collagen type III formulated
for safety and efficacy as an injectible gel. FG-5016 is a
recombinant human collagen type III (rhCIII) developed to replace
animal-derived collagen in a variety of pharmaceutical and medical
device applications. FG-5016 is a highly purified and fully
characterized biomaterial, which is produced using recombinant
methodology in a yeast expression system free of animal components.
This methodology involves the coordinate expression of genes
encoding collagen and encoding prolyl 4-hydroxylase which enables
formation of thermally stable, triple helical collagen.
[0091] Methods for expressing recombinant genes in yeast cells are
well known in the art and are described in many references
including Romanos et al., Yeast 8:423-488, 1992; Cohen et al.,
Nature 366: 698-701, 1993; and A. Wiseman, Genetically Engineered
Proteins and Enzymes From Yeast: Production Control, 1991, Ellis
Norwood Press, New York. Methods for producing triple helical
collagen in yeast cells are described in U.S. Pat. No. 6,451,557.
Triple helical protein products produced in the yeast cells can be
purified from the cells by techniques well known in the art
including standard chromatographic and precipitation techniques
(See, e.g., Miller and Rhodes, Meth Enzymol., 82:33-64, 1982; and
R. L. Trelstad, Native Collagen Fractionation, In: Immunochemistry
of the Extracellular Matrix, vol. 1, H. Furthmayr, ed., CRC Press,
Boca Raton, Fla., 1982, p. 31-41).
[0092] Regardless of the collagen source, preferred collagen and
collagen derivatives for use in the invention are those that are
sized to fit within the lipid vesicles of the invention, e.g., less
than about 800 nm. Because collagen fibrils are 20-150 nm in size,
fibrils rather than fibers (which are 1000-50,000 nm) are
preferred. To maintain collagen in the fibril form, the pH and/or
ionic strength of the solution containing the fibrils can be
appropriately manipulated. A number of methods exist to reduce
collagen size, including an enzymatic breakdown using a protease.
Collagen can also be broken down mechanically. For example,
collagen can be processed mechanically after drying to produce fine
particles that are less than 800 nm in size. Additionally,
extensive hydrolysis of a collagen-containing solution may be used
to prevent fiber formation.
Lipid Vesicles Containing Collagen and/or Hyaluronic Acid
[0093] The invention provides compositions including lipid vesicles
incorporating human collagen (and/or a fragment thereof) or a
collagen derivative, and/or hyaluronic acid. The vesicles
containing the active agent(s) are useful for administering the
active agent(s) to a subject. Any lipid vesicle suitable for
encapsulating collagen and/or hyaluronic acid, and for
administering to the skin of a human subject may be used.
[0094] Vesicles of the invention are vesicles having one or more
lipid bilayer membranes surrounding a cavity. Lipid vesicles for
use in the invention are typically in the range of about 50 to
about 950 nm (e.g., 50, 100, 200, 300, 400, 500, 600, 700, 800,
900, 950 nm) in size. Methods for producing and using lipid
vesicles are well known in the art and are described, e.g., in U.S.
Pat. Nos. 4,917,951 and 5,013,497; Walde P. and Ichikawa S., Biomol
Eng., 18:143-177, 2001; Hunter D. G. and Frisken B. J., Biophys J.,
74:2996-3002, 1998; and Cevc G., Adv Drug Deliv Rev., 56:675-711,
2004.
[0095] Collagen to be encapsulated within lipid vesicles can be any
suitable form, e.g., a preparation of collagen type I, collagen
type III, a mixture of collagen type I and collagen type III, a
collagen derivative, or a combination thereof.
[0096] Hyaluronic acid may be as described above. Vesicles may
contain only collagen or only HA, or a combination thereof. The
compositions of the subject invention may comprise vesicles that
contain only one active agent, or multiple active agents.
[0097] The lipid vesicles of the invention can include
non-phospholipid surfactants. They can also include a
charge-producing agent and a targeting molecule. Thus, vesicles
made of non-phospholipid "membrane mimetic" amphiphiles are useful
in the invention. These are molecules that have a hydrophilic head
group attached to a hydrophobic tail and include long-chain fatty
acids, long-chain alcohols and derivatives, long-chain amino and
glycerolipids. In the bilayers, the fatty acid tails point into the
membrane's interior and the polar head groups point outward. The
polar groups at one surface of the membrane point towards the
vesicle's interior and those at the other surface point toward the
external environment. As a vesicle forms during its manufacture,
any water-soluble molecules that have been added to the water are
incorporated into the aqueous spaces in the interior of the
spheres, whereas any lipid-soluble molecules added during vesicle
formation are incorporated into the core of the vesicles.
[0098] Paucilamellar vesicles that can be formed from many
bio-compatible, single-tailed amphiphiles are preferred for use in
the invention. Such paucilamellar lipid vesicles include
non-phospholipid vesicles having one or several lipid bilayer
membranes surrounding a large amorphous core in which a chemical
entity of interest (i.e., collagen and/or HA) is encapsulated.
[0099] Non-phospholipid paucilamellar lipid vesicles are sold under
the trade name Novasome.RTM. (IGI Inc., Buena, N.J.). Several
Novasome.RTM. formulations exist (e.g., Novasome.RTM. A,
Novasome.RTM. D), Novasome.RTM. Day Cream).
[0100] Novasome.RTM. vesicles are useful for encapsulating chemical
ingredients to aid in formulation, increase delivery to site of
action and stabilize chemical ingredients in the formulation. These
lipid vesicles are generally about 200-700 nanometers in size,
depending upon a wide variety of membrane constituents individually
chosen for each particular purpose. Their size distribution is
uniform, and encapsulation efficiency can be nearly 100% for lipid
cargo and 85% for aqueous materials. Finely divided insoluble
particles (e.g., insoluble pharmaceuticals) can also be
encapsulated.
[0101] Novasome.RTM. vesicles are inherently stable, and can be
tailored to be stable at pH levels ranging from 2-13 as well as
temperature ranges as low as liquid nitrogen to above the boiling
point of water. They can be stable to solvents including alcohols,
ethers, esters, gasoline, diesel and other fuels. They can
encapsulate fragrances and flavors which contain volatile and
fragile ethers, esters, aldehydes, etc. These vesicles can release
their cargo under varying physical and chemical circumstances
including heat, light, pH changes, enzymatic degradation, drying
transmembrane diffusion, etc.
[0102] Protocols for producing and administering Novasome.RTM.
formulations are described, for example, in U.S. Pat. Nos.
4,855,090; 4,911,928; 5,474,848; 5,628,936; 6,387,373; Holick et
al., British Journal of Dermatology 149:1365-2133, 2003; Gupta et
al., Vaccine 14:219-225, 1996; and Wallach D F H and Philippot J.,
New Type of Lipid Vesicle: Novasome.TM. In: Liposome Technology,
2.sup.nd ed., Gregorriadis G., CRC Press, Boca Raton, Fla., 1982,
pp. 141-151; Niemiec et al., Pharmaceutical Research 12:1184-1188,
1995; and Alfieri D R, Cosmetic Dermatology 10:42-52, 1997.
[0103] In one embodiment, the liposomes are those used in "Day
Cream."
[0104] In certain embodiments of the subject invention, the lipid
vesicles (e.g., non-phospholipid paucilamellar lipid vesicles) may
also include targeting molecules, either hydrophilic or
amphiphilic, which can be used to direct the vesicles to a
particular target in order to allow release of the HA, collagen or
collagen derivative from within the vesicle at a specified
biological location. If hydrophilic targeting molecules are used,
they can be coupled directly or via a spacer to an OH residue of
the polyoxyethylene portion of the surfactant, or they can be
coupled, using techniques in the art, to molecules such as palmitic
acid, long chain amines, or phosphatidyl ethanolamine. If spacers
are used, the targeting molecules can be interdigitated into the
hydrophilic core of the bilayer membrane via the acyl chains of
these compounds. Preferred hydrophilic targeting molecules include
monoclonal antibodies, other immunoglobulins, lectins, and peptide
hormones.
[0105] In addition to hydrophilic targeting molecules, it is also
possible to use amphiphilic targeting molecules. Amphiphilic
targeting molecules are normally not chemically coupled to the
surfactant molecules but rather interact with the lipophilic or
hydrophobic portions of the molecules constituting the bilayer
lamellae of the lipid vesicles. Preferred amphiphilic targeting
molecules are neutral glycolipids, galactocerebrosides (e.g., for
hepatic galactosyl receptors), or charged glycolipids such as
gangliosides.
[0106] In some embodiments, charge-producing materials and steroids
such as cholesterol or hydrocortisone or their analogues and
derivatives are used in the formation of the lipid vesicles (e.g.,
paucilamellar lipid vesicles). Preferred charge-producing materials
include negative charge-producing materials such as dicetyl
phosphate, cetyl sulphate, phosphatidic acid, phosphatidyl serine,
oleic acid, palmitic acid, or mixtures thereof. In order to provide
a net positive charge to the vesicles, long chain amines, e.g.,
stearyl amines or oleyl amines, long chain pyridinium compounds,
e.g., cetyl pyridinium chloride, quaternary ammonium compounds, or
mixtures of these can be used. Another example of a positive
charge-producing material is hexadecyl trimethylammonium bromide, a
potent disinfectant.
Preparing Lipid Vesicles
[0107] Lipid vesicles used according to the subject invention can
be any of a large variety of lipid vesicles known in the art and
can be made according to any of a large number of production
methods. Materials and procedures for forming lipid vesicles are
well-known to those skilled in the art. In general, lipids or
lipophilic substances are dissolved in an organic solvent. When the
solvent is removed, such as under vacuum by rotary evaporation, the
lipid residue forms a film on the wall of the container. An aqueous
solution that typically contains electrolytes or hydrophilic
biologically agent materials is then added to the film. Large
multilamellar vesicles are produced upon agitation. When smaller
multilamellar vesicles are desired, the larger vesicles are
subjected to sonication, sequential filtration through filters with
decreasing pore size or reduced by other forms of mechanical
shearing. Lipid vesicles can also take the form of unilamellar
vesicles, which are prepared by more extensive sonication of
multilamellar vesicles, and consist of a single spherical lipid
bilayer surrounding an aqueous solution. A comprehensive review of
all the aforementioned lipid vesicles and methods for their
preparation are described in "Liposome Technology", ed. G.
Gregoriadis, CRC Press Inc., Boca Raton, Fla., Vol. I, II & III
(1984). For methods of preparing lipid vesicles, also see U.S. Pat.
Nos. 4,485,054, 4,761,288, 5,013,497, 5,653,996, and 6,855,
296.
[0108] To prepare non-phospholipid paucilamellar lipid vesicles
formed of non-phospholipid surfactant material and containing an
aqueous-based collagen and/or HA material, any suitable method
known in the art can be used. Methods of preparing non-phospholipid
paucilamellar lipid vesicles typically involve first forming a
lipophilic phase by combining several lipophilic components
including surfactant material and then heating and blending this
mixture. Examples of suitable surfactant materials include but are
not limited to polyoxyethylene (2) cetyl ether, polyoxyethylene (4)
lauryl ether, glyceryl monostearate, and poly oxyethylene (9)
glyceryl stearate. The resultant lipophilic phase is then blended
with an aqueous phase having an aqueous buffer and an aqueous
soluble collagen formulation, under shear mixing conditions, to
form the paucilamellar lipid vesicles. In this method, the
temperature of the lipophilic phase is elevated in order to make it
flowable followed by carrying out the shear mixing between the
lipophilic phase and the aqueous phase at a temperature such that
both phases are liquids. While it is often desirable to use the
same temperature for both phases, this is not always necessary. Any
other method known to the skilled artisan can also be used.
Preferred methods for making the paucilamellar lipid vesicles of
the invention are described in U.S. Pat. No. 4,911,928.
[0109] To encapsulate oil-based collagen or collagen-containing
formulations within paucilamellar lipid vesicles, the collagen or
collagen-containing formulation is dispersed in an oil or wax
forming an oily phase. The oil or wax is a water immiscible oily
solution selected from a group consisting of oils, waxes, natural
and synthetic triglycerides, acyl esters, and petroleum
derivatives, and their analogues and derivatives. The oily phase
containing the oil-dispersible material is mixed with the lipid
phase and the combined oil-lipid phase is blended under shear
mixing conditions with the aqueous phase. Surfactants useful in the
encapsulation process are the same as those used to make
paucilamellar lipid vesicles with an aqueous core.
[0110] Paucilamellar lipid vesicles can be made by a variety of
devices which provide sufficiently high shear for shear mixing.
Many such devices are available on the market including a
Microfluidizer.RTM. such as is made by MicroFluidics Corp. (Newton,
Mass.), a "French"-type press, or some other device which provides
a high enough shear force and the ability to handle heated,
semiviscous lipids. If a very high shear device is used, it may be
possible to microemulsify powdered lipids, under pressure, at a
temperature below their normal melting points and still form the
collagen-containing paucilamellar lipid vesicles of the present
invention.
[0111] A device which is particularly useful for making the
paucilamellar lipid vesicles of the present invention has been
developed by Micro Vesicular Systems, Inc., (Vineland, N.J.) and is
further described in U.S. Pat. No. 4,895,452. Briefly, this device
has a substantially cylindrical mixing chamber with at least one
tangentially located inlet orifice. One or more orifices lead to a
reservoir for the lipophilic phase, mixed with an oil phase if
lipid-core paucilamellar lipid vesicles are to be formed, and at
least one of the other orifices is attached to a reservoir for the
aqueous phase. The different phases are driven into the cylindrical
chamber through pumps, e.g., positive displacement pumps, and
intersect in such a manner as to form a turbulent flow within the
chamber. The paucilamellar lipid vesicles form rapidly, e.g., less
than 1 second, and are removed from the chamber through an axially
located discharge orifice. Preferably, there are four tangentially
located inlet orifices and the lipid and aqueous phases are drawn
from reservoirs, through positive displacement pumps, to
alternating orifices. The fluid stream through the tangential
orifices is guided in a spiral flow path from each inlet or
injection orifice to the discharge orifice. The flow paths are
controlled by the orientation or placement of the inlet or
injection orifices so as to create a mixing zone by the
intersection of the streams of liquid. The pump speeds, as well as
the orifice and feed line diameters, are selected to achieve proper
shear mixing for lipid vesicle formation. In most circumstances,
turbulent flow is selected to provide adequate mixing.
[0112] No matter what device is used to form the paucilamellar
lipid vesicles, if proper shear mixing is achieved they have a
structure involving a large, unstructured amorphous center
surrounded by a plurality of lipid bilayers having aqueous layers
interspersed there between. About four lipid bilayers is standard
with 2-8 possible. The amorphous center may be entirely filled with
an aqueous material, e.g., a buffer and any aqueous material to be
encapsulated, or may be partially or totally filled with an oily
material, forming lipid-core paucilamellar lipid vesicles. If an
aqueous center is used, the paucilamellar lipid vesicles will
normally range in diameter from about 0.5-2.mu. while if an oily
center is used, the size may increase to up to about 15-20.mu.
depending upon the amount of oil used.
Use of Cyclodextin as a Carrier
[0113] Additionally, cyclodextrins are an alternate option for a
collagen and/or HA carrier system into the dermis of the skin.
Cyclodextrins are complex carbohydrates of 6, 7, or 8
D-glucopyranose residues that are linked by 1,4 glycosidic bonds.
The three forms are dependent on the number of D-glucopyranose
residues, the alpha form having 6, beta having 7, and gamma having
8. The alpha structure forms an annular ring with an internal
hydrophobic cavity and a hydrophilic outer surface. Each
cyclodextrin associates with a guest compound by fitting the
compound into the hydrophobic cavity forming an inclusion complex.
In this way cyclodextrins can be used as a delivery system to
deliver a desired amount of material to a target location.
[0114] In one embodiment hydroxypropyl beta cyclodextrins can be
used. Cyclodextrins are used because they have the ability to alter
the physical, chemical, and biological properties of an associated
guest compound through formation of the inclusion complex. This
complex enhances the solubility, stability, and bioavailability of
the guest compound so that the material can be isolated and used in
a controlled delivery system. Formation an inclusion complex of
collagen with an alpha-cyclodextrin allows for a targeted delivery
system to the dermis.
[0115] The principal method for the isolation and purification of
alpha-cyclodextrin takes advantage of its complex-forming ability.
At completion of the reaction, 1-decanol is added to the reaction
mixture to form an insoluble 1:1 alpha-cyclodextrin: 1-decanol
inclusion complex. The complex is continuously mixed with water and
separated from the reaction mixture by centrifugation. The
recovered complex is re-suspended in water and dissolved by
heating. Subsequent cooling leads to re-precipitation of the
complex. The precipitate is recovered by centrifugation, and
1-decanol is removed by steam distillation. Upon cooling,
alpha-cyclodextrin crystallizes from solution. The crystals are
removed by filtration and dried, yielding a white crystalline
powder with a water content under 11%. The purity on a dried basis
is at least 98%.
Dermatologically-Acceptable Carrier
[0116] The topical compositions of the present invention, in
addition to the vesicle-contained collagen and/or HA, can further
comprise a dermatologically acceptable carrier. A safe and
effective amount of carrier is typically from about 50% to about
99.99%, preferably from about 80% to about 99.9%, more preferably
from about 90% to about 98%, and even more preferably from about
90% to about 95% of the composition.
[0117] The carrier can be in a wide variety of forms. For example,
emulsion carriers, including, but not limited to, oil-in-water,
water-in-oil, water-in-oil-in-water, and oil-in-water-in-silicone
emulsions, are useful herein.
[0118] Emulsions according to the present invention can contain a
solution as described above and a lipid or oil. Lipids and oils may
be derived from animals, plants, or petroleum and may be natural or
synthetic (i.e., man-made). Preferred emulsions also contain a
humectant, such as glycerin. Emulsions will preferably further
contain from about 0.01% to about 10%, more preferably from about
0.1% to about 5%, of an emulsifier, based on the weight of the
carrier. Emulsifiers may be nonionic, anionic or cationic. Suitable
emulsifiers are disclosed in, for example, U.S. Pat. No. 3,755,560,
issued Aug. 28, 1973 to Dickert et al.; U.S. Pat. No. 4,421,769,
issued Dec. 20, 1983 to Dixon et al.; and McCutcheon's Detergents
and Emulsifiers, North American Ed., pages 317-324 (1986).
[0119] The emulsion may also contain an anti-foaming agent to
minimize foaming upon application to the epidermal tissue.
Anti-foaming agents include high molecular weight silicones and
other materials well known in the art for such use.
[0120] Suitable emulsions may have a wide range of viscosities,
depending on the desired product form. Exemplary low viscosity
emulsions, which are preferred, have a viscosity of about 50
centistokes or less, more preferably about 10 centistokes or less,
still more preferably about 5 centistokes or less.
[0121] Water-in-silicone emulsions can contain a continuous
silicone phase and a dispersed aqueous phase. The continuous
silicone phase exists as an external phase that contains or
surrounds the discontinuous aqueous phase described hereinafter.
The continuous silicone phase may contain one or more non-silicone
oils. Examples of non-silicone oils suitable for use in the
continuous silicone phase are those well known in the chemical arts
in topical personal care products in the form of water-in-oil
emulsions, e.g., mineral oil, vegetable oils, synthetic oils,
semisynthetic oils, etc.
[0122] In emulsion technology, the term "dispersed phase" is a term
well-known to one skilled in the art that means that the phase
exists as small particles or droplets that are suspended in and
surrounded by a continuous phase. The dispersed phase is also known
as the internal or discontinuous phase. The dispersed aqueous phase
is a dispersion of small aqueous particles or droplets suspended in
and surrounded by the continuous silicone phase described
hereinbefore.
[0123] The aqueous phase can be water, or a combination of water
and one or more water soluble or dispersible ingredients.
Nonlimiting examples of such ingredients include thickeners, acids,
bases, salts, chelants, gums, water-soluble or dispersible alcohols
and polyols, buffers, preservatives, sunscreening agents,
colorings, and the like.
[0124] Water-in-silicone emulsions can contain an emulsifier. In
one embodiment, the composition contains from about 0.1% to about
10% emulsifier, more preferably from about 0.5% to about 7.5%,
still more preferably from about 1% to about 5%, emulsifier by
weight of the composition. The emulsifier helps disperse and
suspend the aqueous phase within the continuous silicone phase.
[0125] Other topical carriers include oil-in-water emulsions,
having a continuous aqueous phase and a hydrophobic,
water-insoluble phase ("oil phase") dispersed therein. Examples of
suitable oil-in-water emulsion carriers are described in U.S. Pat.
No. 5,073,371, to Turner, D. J. et al., issued Dec. 17, 1991, and
U.S. Pat. No. 5,073,372, to Turner, D. J. et al., issued Dec. 17,
1991.
[0126] An oil-in-water emulsion can contain a structuring agent to
assist in the formation of a liquid crystalline gel network
structure. Structuring agents include stearic acid, palmitic acid,
stearyl alcohol, cetyl alcohol, behenyl alcohol, stearic acid,
palmitic acid, the polyethylene glycol ether of stearyl alcohol
having an average of about 1 to about 21 ethylene oxide units, the
polyethylene glycol ether of cetyl alcohol having an average of
about 1 to about 5 ethylene oxide units, and mixtures thereof.
[0127] In certain embodiments, oil-in-water emulsions that contain
at least one hydrophilic surfactant which can disperse the
hydrophobic materials in the water phase (percentages by weight of
the topical carrier). The surfactant, at a minimum, must be
hydrophilic enough to disperse in water. Among the nonionic
surfactants that are useful herein are those that can be broadly
defined as condensation products of long chain alcohols, e.g. C8-30
alcohols, with sugar or starch polymers, i.e., glycosides.
[0128] Other suitable surfactants useful herein include a wide
variety of cationic, anionic, zwitterionic, and amphoteric
surfactants such as are known in the art. See, e.g., McCutcheon's,
Detergents and Emulsifiers, North American Edition (1986),
published by Allured Publishing Corporation; U.S. Pat. No.
5,011,681 to Ciotti et al., issued Apr. 30, 1991;
[0129] U.S. Pat. No. 4,421,769 to Dixon et al., issued Dec. 20,
1983; and U.S. Pat. No. 3,755,560 to Dickert et al., issued Aug.
28, 1973; these four references are incorporated herein by
reference in their entirety. The hydrophilic surfactants useful
herein can contain a single surfactant, or any combination of
suitable surfactants. The exact surfactant (or surfactants) chosen
will depend upon the pH of the composition and the other components
present.
[0130] Also useful herein are cationic surfactants, such as dialkyl
quaternary ammonium compounds, examples of which are described in
U.S. Pat. Nos. 5,151,209; 5,151,210; 5,120,532; 4,387,090;
3,155,591; 3,929,678; 3,959,461; McCutcheon's, Detergents &
Emulsifiers, (North American edition 1979) M.C. Publishing Co.; and
Schwartz, et al., Surface Active Agents, Their Chemistry and
Technology, New York: Interscience Publishers, 1949; which
descriptions are incorporated herein by reference.
[0131] A wide variety of anionic surfactants are also useful
herein. See, e.g., U.S. Pat. No. 3,929,678, to Laughlin et al.,
issued Dec. 30, 1975, which is incorporated herein by reference in
its entirety. Nonlimiting examples of anionic surfactants include
the alkoyl isethionates, and the alkyl and alkyl ether
sulfates.
[0132] Examples of amphoteric and zwitterionic surfactants are
those which are broadly described as derivatives of aliphatic
secondary and tertiary amines in which the aliphatic radical can be
straight or branched chain and wherein one of the aliphatic
substituents contains from about 8 to about 22 carbon atoms
(preferably C.sub.8-C.sub.18) and one contains an anionic water
solubilizing group, e.g., carboxy, sulfonate, sulfate, phosphate,
or phosphonate.
[0133] The topical compositions of the subject invention, including
but not limited to lotions and creams, may contain a
dermatologically acceptable emollient. Such compositions preferably
contain from about 1% to about 50% of the emollient. As used
herein, "emollient" refers to a material useful for the prevention
or relief of dryness, as well as for the protection of the skin. A
wide variety of suitable emollients are known and may be used
herein. Sagarin, Cosmetics, Science and Technology, 2nd Edition,
Vol. 1, pp. 32-43 (1972), incorporated herein by reference,
contains numerous examples of materials suitable as an emollient. A
preferred emollient is glycerin. Glycerin is preferably used in an
amount of from or about 0.001 to or about 30%, more preferably from
or about 0.01 to or about 20%, still more preferably from or about
0.1 to or about 10%, e.g., 5%.
[0134] Creams are generally thicker than lotions due to higher
levels of emollients or higher levels of thickeners.
[0135] Ointments of the present invention may contain a simple
carrier base of animal or vegetable oils or semi-solid hydrocarbons
(oleaginous); absorption ointment bases which absorb water to form
emulsions; or water soluble carriers, e.g., a water soluble
solution carrier. Ointments may further contain a thickening agent,
such as described in Sagarin, Cosmetics, Science and Technology,
2nd Edition, Vol. 1, pp. 72-73 (1972), incorporated herein by
reference, and/or an emollient. For example, an ointment may
contain from about 2% to about 10% of an emollient; from about 0.1%
to about 2% of a thickening agent; and the vesicle-collagen in the
above described amounts.
Additional Skin Care Agents
[0136] The compositions of the present invention may contain one or
more additional skin care agents, in addition to collagen and/or
HA, the agents enumerated below do not include water unless
specifically stated.
[0137] The additional agents should be suitable for application to
epidermal tissue, that is, when incorporated into the composition
they are suitable for use in contact with human epidermal tissue
without undue toxicity, incompatibility, instability, allergic
response, and the like. The CTFA Cosmetic Ingredient Handbook,
Second Edition (1992) describes a wide variety of nonlimiting
cosmetic and pharmaceutical ingredients commonly used in the skin
care industry, which are suitable for use in the compositions of
the present invention.
[0138] Examples of such ingredient classes include: abrasives,
absorbents, aesthetic components such as fragrances, pigments,
colorings/colorants, essential oils, skin sensates, astringents,
etc. (e.g., clove oil, menthol, camphor, eucalyptus oil, eugenol,
menthyl lactate, witch hazel distillate), anti-acne agents,
anti-caking agents, antifoaming agents, antimicrobial agents (e.g.,
iodopropyl butylcarbamate), antioxidants, binders, biological
additives, buffering agents, bulking agents, chelating agents,
chemical additives, colorants, cosmetic astringents, cosmetic
biocides, denaturants, drug astringents, external analgesics, film
formers or materials, e.g., polymers, for aiding the film-forming
properties and substantivity of the composition (e.g., copolymer of
eicosene and vinyl pyrrolidone), opacifying agents, pH adjusters,
propellants, reducing agents, sequestrants, skin bleaching and
lightening agents (e.g., hydroquinone, kojic acid, ascorbic acid,
magnesium ascorbyl phosphate, ascorbyl glucosamine),
skin-conditioning agents (e.g., humectants, including miscellaneous
and occlusive), skin soothing and/or healing agents (e.g.,
panthenol and derivatives (e.g., ethyl panthenol), aloe vera,
pantothenic acid and its derivatives, allantoin, bisabolol, and
dipotassium glycyrrhizinate), skin treating agents, thickeners, and
vitamins and derivatives thereof.
[0139] In any embodiment of the present invention, however, the
agents useful herein can be categorized by the benefit they provide
or by their postulated mode of action. However, it is to be
understood that the additional agents for use herein can in some
instances provide more than one benefit or operate via more than
one mode of action. Therefore, classifications herein are made for
the sake of convenience and are not intended to limit the agent to
that particular application or applications listed.
[0140] Desquamation Agents A safe and effective amount of a
desquamation agent may be added to the compositions of the present
invention, more preferably from about 0.1% to about 10%, even more
preferably from about 0.2% to about 5%, also preferably from about
0.5% to about 4%, by weight of the composition. Desquamation agents
enhance the skin appearance benefits of the present invention. For
example, the desquamation agents tend to improve the texture of the
skin (e.g., smoothness). One desquamation system that is suitable
for use herein contains sulfhydryl compounds and zwitterionic
surfactants and is described in U.S. Pat. No. 5,681,852, to
Bissett, incorporated herein by reference. Another desquamation
system that is suitable for use herein contains salicylic acid and
zwitterionic surfactants and is described in U.S. Pat. No.
5,652,228 to Bissett, incorporated herein by reference.
Zwitterionic surfactants such as described in these applications
are also useful as desquamatory agents herein, with cetyl betaine
being particularly preferred.
[0141] Anti-Acne Agents The compositions of the present invention
may contain a safe and effective amount of one or more anti-acne
agents. Examples of useful anti-acne agents include resorcinol,
sulfur, salicylic acid, benzoyl peroxide, erythromycin, zinc, etc.
Further examples of suitable anti-acne agents are described in
further detail in U.S. Pat. No. 5,607,980, issued to McAtee et al,
on Mar. 4, 1997.
Anti-Wrinkle Agents/Anti-Atrophy Agents
[0142] The compositions of the present invention may further
contain a safe and effective amount of one or more anti-wrinkle
agents or anti-atrophy agents. Exemplary anti-wrinkle/anti-atrophy
agents suitable for use in the compositions of the present
invention include sulfur-containing D and L amino acids and their
derivatives and salts, particularly the N-acetyl derivatives, a
preferred example of which is N-acetyl-L-cysteine; thiols, e.g.
ethane thiol; hydroxy acids (e.g., alpha-hydroxy acids such as
lactic acid and glycolic acid or beta-hydroxy acids such as
salicylic acid and salicylic acid derivatives such as the octanoyl
derivative), phytic acid, lipoic acid; lysophosphatidic acid, skin
peel agents (e.g., phenol and the like), vitamin B.sub.3 compounds,
retinoids, and hyaluronic acid, which enhance the epidermal tissue
appearance benefits of the present invention, especially in
regulating epidermal tissue condition, e.g., skin condition.
Vitamin B.sub.3 Compounds
[0143] The compositions of the present invention may contain a safe
and effective amount of a vitamin B.sub.3 compound. Vitamin B.sub.3
compounds are particularly useful for regulating skin condition as
described in U.S. application Ser. No. 08/834,010, filed Apr. 11,
1997 (corresponding to international publication WO 97/39733 A1,
published Oct. 30, 1997). Examples of suitable vitamin B.sub.3
compounds are well known in the art and are commercially available
from a number of sources, e.g., the Sigma Chemical Company (St.
Louis, Mo.); ICN Biomedicals, Inc. (Irvin, Calif.) and Aldrich
Chemical Company (Milwaukee, Wis.). The vitamin compounds may be
included as the substantially pure material, or as an extract
obtained by suitable physical and/or chemical isolation from
natural (e.g., plant) sources.
Retinoids
[0144] The compositions of the present invention may also contain a
retinoid. As used herein, "retinoid" includes all natural and/or
synthetic analogs of Vitamin A or retinol-like compounds which
possess the biological activity of Vitamin A in the skin as well as
the geometric isomers and stereoisomers of these compounds. The
retinoid is preferably retinol, retinol esters (e.g., C.sub.2
-C.sub.22 alkyl esters of retinol, including retinyl palmitate,
retinyl acetate, retinyl propionate), retinal, and/or retinoic acid
(including all-trans retinoic acid and/or 13-cis-retinoic acid),
more preferably retinoids other than retinoic acid. These compounds
are well known in the art and are commercially available from a
number of sources, e.g., Sigma Chemical Company (St. Louis, Mo.),
and Boerhinger Mannheim (Indianapolis, Ind.). Other retinoids which
are useful herein are described in U.S. Pat. No. 4,677,120, issued
Jun. 30, 1987 to Parish et al.; U.S. Pat. No. 4,885,311, issued
Dec. 5, 1989 to Parish et al.; U.S. Pat. No. 5,049,584, issued Sep.
17, 1991 to Purcell et al.; U.S. Pat. No. 5,124,356, issued Jun.
23, 1992 to Purcell et al.; and U.S. Pat. No. Reissue 34,075,
issued Sep. 22, 1992 to Purcell et al. Other suitable retinoids are
tocopheryl-retinoate [tocopherol ester of retinoic acid (trans- or
cis-), adapalene {6-[3-(1-adamantyl)-4-methoxyphenyl]-2-naphthoic
acid}, and tazarotene (ethyl
6-[2-(4,4-dimethylthiochroman-6-yl)-ethynyl]nicotinate). Preferred
retinoids are retinol, retinyl palmitate, retinyl acetate, retinyl
propionate, retinal and combinations thereof.
Hydroxy Acids
[0145] The compositions of the present invention may contain a safe
and effective amount of a hydroxy acid. Preferred hydroxy acids for
use in the compositions of the present invention include salicylic
acid and salicylic acid derivatives.
Anti-Oxidants/Radical Scavengers
[0146] The compositions of the present invention may include a safe
and effective amount of an anti-oxidant/radical scavenger. The
anti-oxidant/radical scavenger is especially useful for providing
protection against UV radiation which can cause increased scaling
or texture changes in the stratum corneum and against other
environmental agents which can cause skin damage.
[0147] A safe and effective amount of an anti-oxidant/radical
scavenger may be added to the compositions of the subject
invention, preferably from about 0.1% to about 10%, more preferably
from about 1% to about 5%, of the composition.
[0148] Anti-oxidants/radical scavengers such as ascorbic acid
(vitamin C) and its salts, ascorbyl esters of fatty acids, ascorbic
acid derivatives (e.g., magnesium ascorbyl phosphate, sodium
ascorbyl phosphate, ascorbyl sorbate), tocopherol (vitamin E),
tocopherol sorbate, tocopherol acetate, other esters of tocopherol,
butylated hydroxy benzoic acids and their salts,
6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid
(commercially available under the tradename Troloxg.RTM., gallic
acid and its alkyl esters, especially propyl gallate, uric acid and
its salts and alkyl esters, sorbic acid and its salts, lipoic acid,
amines (e.g., N,N-diethylhydroxylamine, amino-guanidine),
sulfhydryl compounds (e.g., glutathione), dihydroxy fumaric acid
and its salts, lycine pidolate, arginine pilolate,
nordihydroguaiaretic acid, bioflavonoids, curcumin, lysine,
methionine, proline, superoxide dismutase, silymarin, tea extracts,
grape skin/seed extracts, melanin, and rosemary extracts may be
used. Preferred anti-oxidants/radical scavengers are selected from
tocopherol sorbate and other esters of tocopherol, more preferably
tocopherol sorbate. For example, the use of tocopherol sorbate in
topical compositions and applicable to the present invention is
described in U.S. Pat. No. 4,847,071, issued on Jul. 11, 1989 to
Donald L. Bissett, Rodney D. Bush and Ranjit Chatterjee.
Chelators
[0149] The compositions of the present invention may also contain a
safe and effective amount of a chelator or chelating agent. As used
herein, "chelator" or "chelating agent" means an active agent
capable of removing a metal ion from a system by forming a complex
so that the metal ion cannot readily participate in or catalyze
chemical reactions. The inclusion of a chelating agent is
especially useful for providing protection against UV radiation
which can contribute to excessive scaling or skin texture changes
and against other environmental agents which can cause skin
damage.
[0150] A safe and effective amount of a chelating agent may be
added to the compositions of the subject invention, preferably from
about 0.1% to about 10%, more preferably from about 1% to about 5%,
of the composition. Exemplary chelators that are useful herein are
disclosed in U.S. Pat. No. 5,487,884, issued Jan. 30, 1996 to
Bissett et al.; International Publication No. 91/16035, Bush et
al., published Oct. 31, 1995; and International Publication No.
91/16034, Bush et al., published Oct. 31, 1995. Preferred chelators
useful in compositions of the subject invention are furildioxime,
furilmonoxime, and derivatives thereof.
Flavonoids
[0151] The compositions of the present invention may optionally
contain a flavonoid compound. Flavonoids are broadly disclosed in
U.S. Pat. Nos. 5,686,082 and 5,686,367, both of which are herein
incorporated by reference. Flavonoids suitable for use in the
present invention are flavanones selected from unsubstituted
flavanones, mono-substituted flavanones, and mixtures thereof;
chalcones selected from unsubstituted chalcones, mono-substituted
chalcones, di-substituted chalcones, tri-substituted chalcones, and
mixtures thereof; flavones selected from unsubstituted flavones,
mono-substituted flavones, di-substituted flavones, and mixtures
thereof; one or more isoflavones; coumarins selected from
unsubstituted coumarins, mono-substituted coumarins, di-substituted
coumarins, and mixtures thereof; chromones selected from
unsubstituted chromones, mono-substituted chromones, di-substituted
chromones, and mixtures thereof; one or more dicoumarols; one or
more chromanones; one or more chromanols; isomers (e.g., cis/trans
isomers) thereof; and mixtures thereof. By the term "substituted"
as used herein means flavonoids wherein one or more hydrogen atom
of the flavonoid has been independently replaced with hydroxyl,
C1-C8 alkyl, C1-C4 alkoxyl, 0-glycoside, and the like or a mixture
of these substituents.
[0152] Examples of suitable flavonoids include, but are not limited
to, unsubstituted flavanone, mono-hydroxy flavanones (e.g.,
2'-hydroxy flavanone, 6-hydroxy flavanone, 7-hydroxy flavanone,
etc.), mono-alkoxy flavanones (e.g., 5-methoxy flavanone, 6-methoxy
flavanone, 7-methoxy flavanone, 4'-methoxy flavanone, etc.),
unsubstituted chalcone (especially unsubstituted trans-chalcone),
mono-hydroxy chalcones (e.g., 2'-hydroxy chalcone, 4'-hydroxy
chalcone, etc.), di-hydroxy chalcones (e.g., 2',4-dihydroxy
chalcone, 2',4'-dihydroxy chalcone, 2,2'-dihydroxy chalcone,
2',3-dihydroxy chalcone, 2',5'-dihydroxy chalcone, etc.), and
tri-hydroxy chalcones (e.g., 2',3',4'-trihydroxy chalcone,
4,2',4'-trihydroxy chalcone, 2,2',4'-trihydroxy chalcone, etc.),
unsubstituted flavone, 7,2'-dihydroxy flavone, 3',4'-dihydroxy
naphthoflavone, 4'-hydroxy flavone, 5,6-benzoflavone, and
7,8-benzoflavone, unsubstituted isoflavone, daidzein
(7,4'-dihydroxy isoflavone), 5,7-dihydroxy-4'-methoxy isoflavone,
soy isoflavones (a mixture extracted from soy), unsubstituted
coumarin, 4-hydroxy coumarin, 7-hydroxy coumarin,
6-hydroxy-4-methyl coumarin, unsubstituted chromone, 3-formyl
chromone, 3-formyl-6-isopropyl chromone, unsubstituted dicoumarol,
unsubstituted chromanone, unsubstituted chromanol, and mixtures
thereof.
[0153] Preferred for use herein are unsubstituted flavanone,
methoxy flavanones, unsubstituted chalcone, 2',4-dihydroxy
chalcone, and mixtures thereof. More preferred are unsubstituted
flavanone, unsubstituted chalcone (especially the trans isomer),
and mixtures thereof.
[0154] They can be synthetic materials or obtained as extracts from
natural sources (e.g., plants). The naturally sourced material can
also further be derivatized (e.g., an ester or ether derivative
prepared following extraction from a natural source). Flavonoid
compounds useful herein are commercially available from a number of
sources, e.g., Indofine Chemical Company, Inc. (Somerville, N.J.),
Steraloids, Inc. (Wilton, N.H.), and Aldrich Chemical Company, Inc.
(Milwaukee, Wis.).
Anti-Inflammatory Agents
[0155] A safe and effective amount of an anti-inflammatory agent
may be added to the compositions of the present invention,
preferably from about 0.1% to about 10%, more preferably from about
0.5% to about 5%, of the composition. The anti-inflammatory agent
enhances the skin appearance benefits of the present invention,
e.g., such agents contribute to a more uniform and acceptable skin
tone or color. The exact amount of anti-inflammatory agent to be
used in the compositions will depend on the particular
anti-inflammatory agent utilized since such agents vary widely in
potency.
[0156] Steroidal anti-inflammatory agents, including but not
limited to, corticosteroids such as hydrocortisone,
hydroxyltriamcinolone, alpha-methyl dexamethasone,
dexamethasone-phosphate, beclomethasone dipropionates, clobetasol
valerate, desonide, desoxymethasone, desoxycorticosterone acetate,
dexamethasone, dichlorisone, diflorasone diacetate, diflucortolone
valerate, fluadrenolone, fluclorolone acetonide, fludrocortisone,
flumethasone pivalate, fluosinolone acetonide, fluocinonide,
flucortine butylesters, fluocortolone, fluprednidene
(fluprednylidene) acetate, flurandrenolone, halcinonide,
hydrocortisone acetate, hydrocortisone butyrate,
methylprednisolone, triamcinolone acetonide, cortisone,
cortodoxone, flucetonide, fludrocortisone, difluorosone diacetate,
fluradrenolone, fludrocortisone, diflurosone diacetate,
fluradrenolone acetonide, medrysone, amcinafel, amcinafide,
betamethasone and the balance of its esters, chloroprednisone,
chlorprednisone acetate, clocortelone, clescinolone, dichlorisone,
diflurprednate, flucloronide, flunisolide, fluoromethalone,
fluperolone, fluprednisolone, hydrocortisone valerate,
hydrocortisone cyclopentylpropionate, hydrocortamate, meprednisone,
paramethasone, prednisolone, prednisone, beclomethasone
dipropionate, triamcinolone, and mixtures thereof may be used. The
preferred steroidal anti-inflammatory for use is
hydrocortisone.
[0157] A second class of anti-inflammatory agents which is useful
in the compositions includes the nonsteroidal anti-inflammatory
agents. The variety of compounds encompassed by this group are
well-known to those skilled in the art. For detailed disclosure of
the chemical structure, synthesis, side effects, etc. of
non-steroidal anti-inflammatory agents, one may refer to standard
texts, including Anti-inflammatory and Anti-Rheumatic Drugs, K. D.
Rainsford, Vol. I-III, CRC Press, Boca Raton, (1985), and
Anti-inflammatory Agents, Chemistry and Pharmacology, 1, R. A.
Scherrer, et al., Academic Press, New York (1974).
[0158] Specific non-steroidal anti-inflammatory agents useful in
the composition invention include, but are not limited to:
[0159] 1) the oxicams, such as piroxicam, isoxicam, tenoxicam,
sudoxicam, and CP-14,304;
[0160] 2) the salicylates, such as aspirin, disalcid, benorylate,
trilisate, safapryn, solprin, diflunisal, and fendosal;
[0161] 3) the acetic acid derivatives, such as diclofenac,
fenclofenac, indomethacin, sulindac, tolmetin, isoxepac, furofenac,
tiopinac, zidometacin, acematacin, fentiazac, zomepirac, clindanac,
oxepinac, felbinac, and ketorolac;
[0162] 4) the fenamates, such as mefenamic, meclofenamic,
flufenamic, niflumic, and tolfenamic acids;
[0163] 5) the propionic acid derivatives, such as ibuprofen,
naproxen, benoxaprofen, flurbiprofen, ketoprofen, fenoprofen,
fenbufen, indopropfen, pirprofen, carprofen, oxaprozin,
pranoprofen, miroprofen, tioxaprofen, suprofen, alminoprofen, and
tiaprofenic; and
[0164] 6) the pyrazoles, such as phenylbutazone, oxyphenbutazone,
feprazone, azapropazone, and trimethazone.
[0165] Mixtures of these non-steroidal anti-inflammatory agents may
also be employed, as well as the dermatologically acceptable salts
and esters of these agents. For example, etofenamate, a flufenamic
acid derivative, is particularly useful for topical application. Of
the nonsteroidal anti-inflammatory agents, ibuprofen, naproxen,
flufenamic acid, etofenamate, aspirin, mefenamic acid, meclofenamic
acid, piroxicam and felbinac are preferred; ibuprofen, naproxen,
ketoprofen, etofenamate, aspirin and flufenamic acid are more
preferred.
[0166] Finally, so-called "natural" anti-inflammatory agents are
useful in methods of the present invention. Such agents may
suitably be obtained as an extract by suitable physical and/or
chemical isolation from natural sources (e.g., plants, fungi,
by-products of microorganisms) or can be synthetically prepared.
For example, candelilla wax, bisabolol (e.g., alpha bisabolol),
aloe vera, plant sterols (e.g., phytosterol), Manjistha (extracted
from plants in the genus Rubia, particularly Rubia Cordifolia), and
Guggal (extracted from plants in the genus Commiphora, particularly
Commiphora Mukul), kola extract, chamomile, red clover extract, and
sea whip extract, may be used.
[0167] Additional anti-inflammatory agents useful herein include
compounds of the Licorice (the plant genus/species Glycyrrhiza
glabra) family, including glycyrrhetic acid, glycyrrhizic acid, and
derivatives thereof (e.g., salts and esters). Suitable salts of the
foregoing compounds include metal and ammonium salts. Suitable
esters include C.sub.2-C.sub.24 saturated or unsaturated esters of
the acids, preferably C.sub.10-C.sub.24, more preferably
C.sub.16-C.sub.24. Specific examples of the foregoing include oil
soluble licorice extract, the glycyrrhizic and glycyrrhetic acids
themselves, monoammonium glycyrrhizinate, monopotassium
glycyrrhizinate, dipotassium glycyrrhizinate, 1-beta-glycyrrhetic
acid, stearyl glycyrrhetinate, and 3-stearyloxy-glycyrrhetinic
acid, and disodium 3-succinyloxy-beta-glycyrrhetinate. Stearyl
glycyrrhetinate is preferred.
Anti-Cellulite Agents
[0168] The compositions of the present invention may also contain a
safe and effective amount of an anti-cellulite agent. Suitable
agents may include, but are not limited to, xanthine compounds
(e.g., caffeine, theophylline, theobromine, and aminophylline).
Topical Anesthetics
[0169] The compositions of the present invention may also contain a
safe and effective amount of a topical anesthetic. Examples of
topical anesthetic drugs include benzocaine, lidocaine,
bupivacaine, chlorprocaine, dibucaine, etidocaine, mepivacaine,
tetracaine, dyclonine, hexylcaine, procaine, cocaine, ketamine,
pramoxine, phenol, and pharmaceutically acceptable salts
thereof.
Tanning Agents
[0170] The compositions of the present invention may contain a
tanning agent. When present, it is preferable that the compositions
contain from about 0.1% to about 20%, more preferably from about 2%
to about 7%, and still more preferably from about 3% to about 6%,
by weight of the composition, of dihydroxyacetone as an artificial
tanning agent.
Skin Lightening Agents
[0171] The compositions of the present invention may contain a skin
lightening agent. When used, the compositions preferably contain
from about 0.1% to about 10%, more preferably from about 0.2% to
about 5%, also preferably from about 0.5% to about 2%, by weight of
the composition, of a skin lightening agent. Suitable skin
lightening agents include those known in the art, including kojic
acid, arbutin, ascorbic acid and derivatives thereof (e.g.,
magnesium ascorbyl phosphate or sodium ascorbyl phosphate), and
extracts (e.g., mulberry extract, placental extract). Skin
lightening agents suitable for use herein also include those
described in the PCT publication No. 95/34280, in the name of
Hillebrand, corresponding to PCT Application No. U.S. 95/07432,
filed Jun. 12, 1995; and co-pending U.S. application Ser. No.
08/390,152 filed in the names of Kvalnes, Mitchell A. DeLong,
Barton J. Bradbury, Curtis B. Motley, and John D. Carter,
corresponding to PCT Publication No. 95/23780, published Sep. 8,
1995.
Skin Soothing and Skin Healing Agents
[0172] The compositions of the present invention may comprise a
skin soothing or skin healing agent. Skin soothing or skin healing
agents suitable for use herein include panthenoic acid derivatives
(including panthenol, dexpanthenol, ethyl panthenol), aloe vera,
allantoin, bisabolol, and dipotassium glycyrrhizinate. A safe and
effective amount of a skin soothing or skin healing agent may be
added to the present composition, preferably, from about 0.1% to
about 30%, more preferably from about 0.5% to about 20%, still more
preferably from about 0.5% to about 10%, by weight of the
composition formed.
Antimicrobial and Antifungal Agents
[0173] The compositions of the present invention may contain an
antimicrobial or antifungal agent. Such agents are capable of
destroying microbes, preventing the development of microbes or
preventing the pathogenic action of microbes. A safe and effective
amount of an antimicrobial or antifungal agent may be added to the
present compositions, preferably, from about 0.001% to about 10%,
more preferably from about 0.01% to about 5%, and still more
preferably from about 0.05% to about 2%.
[0174] Examples of antimicrobial and antifungal agents include
B-lactam drugs, quinolone drugs, ciprofloxacin, norfloxacin,
tetracycline, erythromycin, amikacin, 2,4,4'-trichloro-2'-hydroxy
diphenyl ether, 3,4,4'-trichlorobanilide, phenoxyethanol, phenoxy
propanol, phenoxyisopropanol, doxycycline, capreomycin,
chlorhexidine, chlortetracycline, oxytetracycline, clindamycin,
ethambutol, hexamidine isethionate, metronidazole, pentamidine,
gentamicin, kanamycin, lineomycin, methacycline, methenamine,
minocycline, neomycin, netilmicin, paromomycin, streptomycin,
tobramycin, miconazole, tetracycline hydrochloride, erythromycin,
zinc erythromycin, erythromycin estolate, erythromycin stearate,
amikacin sulfate, doxycycline hydrochloride, capreomycin sulfate,
chlorhexidine gluconate, chlorhexidine hydrochloride,
chlortetracycline hydrochloride, oxytetracycline hydrochloride,
clindamycin hydrochloride, ethambutol hydrochloride, metronidazole
hydrochloride, pentamidine hydrochloride, gentamicin sulfate,
kanamycin sulfate, lineomycin hydrochloride, methacycline
hydrochloride, methenamine hippurate, methenamine mandelate,
minocycline hydrochloride, neomycin sulfate, netilmicin sulfate,
paromomycin sulfate, streptomycin sulfate, tobramycin sulfate,
miconazole hydrochloride, ketaconazole, amanfadine hydrochloride,
amanfadine sulfate, octopirox, parachlorometa xylenol, nystatin,
tolnaftate, zinc pyrithione and clotrimazole.
[0175] Additionally antimicrobial peptides can be used.
Sunscreen Agents
[0176] Exposure to ultraviolet light can result in excessive
scaling and texture changes of the stratum corneum. Therefore, the
compositions of the subject invention may optionally contain a
sunscreen agent. As used herein, "sunscreen agent" includes both
sunscreen agents and physical sunblocks. Suitable sunscreen agents
may be organic or inorganic.
[0177] Inorganic sunscreens useful herein include the following
metallic oxides; titanium dioxide having an average primary
particle size of from about 15 nm to about 100 nm, zinc oxide
having an average primary particle size of from about 15 nm to
about 150 nm, zirconium oxide having an average primary particle
size of from about 15 nm to about 150 nm, iron oxide having an
average primary particle size of from about 15 nm to about 500 nm,
and mixtures thereof. When used herein, the inorganic sunscreens
are present in the amount of from about 0.1% to about 20%,
preferably from about 0.5% to about 10%, more preferably from about
1% to about 5%, by weight of the composition.
[0178] A wide variety of conventional organic sunscreen agents are
suitable for use herein. Sagarin, et al., at Chapter VIII, pages
189 et seq., of Cosmetics Science and Technology (1972), discloses
numerous suitable agents. Specific suitable sunscreen agents
include, for example: p-aminobenzoic acid, its salts and its
derivatives (ethyl, isobutyl, glyceryl esters;
p-dimethylaminobenzoic acid); anthranilates (i.e.,
o-amino-benzoates; methyl, menthyl, phenyl, benzyl, phenylethyl,
linalyl, terpinyl, and cyclohexenyl esters); salicylates (amyl,
phenyl, octyl, benzyl, menthyl, glyceryl, and di-pro-pyleneglycol
esters); cinnamic acid derivatives (menthyl and benzyl esters,
a-phenyl cinnamonitrile; butyl cinnamoyl pyruvate);
dihydroxycinnamic acid derivatives (umbelliferone,
methylumbelliferone, methylaceto-umbelliferone);
trihydroxy-cinnamic acid derivatives (esculetin, methylesculetin,
daphnetin, and the glucosides, esculin and daphnin); hydrocarbons
(diphenylbutadiene, stilbene); dibenzalacetone and
benzalacetophenone; naphtholsulfonates (sodium salts of
2-naphthol-3,6-disulfonic and of 2-naphthol-6,8-disulfonic acids);
di-hydroxynaphthoic acid and its salts; o- and
p-hydroxybiphenyldisulfonates; coumarin derivatives (7-hydroxy,
7-methyl, 3-phenyl); diazoles (2-acetyl-3-bromoindazole, phenyl
benzoxazole, methyl naphthoxazole, various aryl benzothiazoles);
quinine salts (bisulfate, sulfate, chloride, oleate, and tannate);
quinoline derivatives (8-hydroxyquinoline salts,
2-phenylquinoline); hydroxy- or methoxy-substituted benzophenones;
uric and violuric acids; tannic acid and its derivatives (e.g.,
hexaethylether); (butyl carbotol) (6-propyl piperonyl) ether;
hydroquinone; benzophenones (oxybenzene, sulisobenzone,
dioxybenzone, benzoresorcinol, 2,2',4,4'-tetrahydroxybenzophenone,
2,2'-dihydroxy-4,4'-dimethoxybenzophenone, octabenzone;
4-isopropyldibenzoylmethane; butylmethoxydibenzoylmethane;
etocrylene; octocrylene; [3-(4'-methylbenzylidene bornan-2-one),
terephthalylidene dicamphor sulfonic acid and
4-isopropyl-di-benzoylmethane.
Conditioning Agents
[0179] The compositions of the present invention may contain a
conditioning agent selected from humectants, moisturizers, or skin
conditioners. A variety of these materials can be employed and each
can be present at a level of from about 0.01% to about 20%, more
preferably from about 0.1% to about 10%, and still more preferably
from about 0.5% to about 7% by weight of the composition. These
materials include, but are not limited to, guanidine; urea;
glycolic acid and glycolate salts (e.g. ammonium and quaternary
alkyl ammonium); salicylic acid; lactic acid and lactate salts
(e.g., ammonium and quaternary alkyl ammonium); aloe vera in any of
its variety of forms (e.g., aloe vera gel); polyhydroxy alcohols
such as sorbitol, mannitol, xylitol, erythritol, glycerol,
hexanetriol, butanetriol, propylene glycol, butylene glycol,
hexylene glycol and the like; polyethylene glycols; sugars (e.g.,
melibiose) and starches; sugar and starch derivatives (e.g.,
alkoxylated glucose, fucose, glucosamine); hyaluronic acid;
lactamide monoethanolamine; acetamide monoethanolamine; panthenol;
allantoin; and mixtures thereof. Also useful herein are the
propoxylated glycerols described in U.S. Pat. No. 4,976,953, to Orr
et al, issued Dec. 11, 1990.
Structuring Agents
[0180] The compositions hereof, and especially the emulsions
hereof, may contain a structuring agent. Structuring agents are
particularly preferred in the oil-in-water emulsions of the present
invention. Without being limited by theory, it is believed that the
structuring agent assists in providing rheological characteristics
to the composition which contribute to the stability of the
composition. For example, the structuring agent tends to assist in
the formation of the liquid crystalline gel network structures. The
structuring agent may also function as an emulsifier or surfactant.
Preferred compositions of this invention contain from about 0.1% to
about 20%, more preferably from about 0.1% to about 10%, still more
preferably from about 0.5% to about 9%, of one or more structuring
agents.
[0181] The preferred structuring agents of the present invention
are selected from stearic acid, palmitic acid, stearyl alcohol,
cetyl alcohol, behenyl alcohol, stearic acid, palmitic acid, the
polyethylene glycol ether of stearyl alcohol having an average of
about 1 to about 5 ethylene oxide units, the polyethylene glycol
ether of cetyl alcohol having an average of about 1 to about 5
ethylene oxide units, and mixtures thereof. More preferred
structuring agents of the present invention are selected from
stearyl alcohol, cetyl alcohol, behenyl alcohol, the polyethylene
glycol ether of stearyl alcohol having an average of about 2
ethylene oxide units (steareth-2), the polyethylene glycol ether of
cetyl alcohol having an average of about 2 ethylene oxide units,
and mixtures thereof. Even more preferred structuring agents are
selected from stearic acid, palmitic acid, stearyl alcohol, cetyl
alcohol, behenyl alcohol, steareth-2, and mixtures thereof.
Thickening Agent (Including Thickeners and Gelling Agents)
[0182] The compositions of the present invention can contain one or
more thickening agents, preferably from about 0.1% to about 5%,
more preferably from about 0.1% to about 4%, and still more
preferably from about 0.25% to about 3%, by weight of the
composition.
[0183] Nonlimiting classes of thickening agents for use in the
compositions of the invention include those selected from the
following: carboxylic acid polymers (such as those described in
U.S. Pat. No. 5,087,445, to Haffey et al, issued Feb. 11, 1992;
U.S. Pat. No. 4,509,949, to Huang et al, issued Apr. 5, 1985; U.S.
Pat. No. 2,798,053, to Brown, issued Jul. 2, 1957; and in CTFA
International Cosmetic Ingredient Dictionary, Fourth Edition, 1991,
pp. 12 and 80); crosslinked polyacrylate polymers (such as those
described in U.S. Pat. No. 5,100,660, to Hawe et al, issued Mar.
31, 1992; U.S. Pat. No. 4,849,484, to Heard, issued Jul. 18, 1989;
U.S. Pat. No. 4,835,206, to Farrar et al, issued May 30, 1989; U.S.
Pat. No. 4,628,078 to Glover et al issued Dec. 9, 1986; U.S. Pat.
No. 4,599,379 to Flesher et al issued Jul. 8, 1986; and EP 228,868,
to Farrar et al, published Jul. 15, 1987); polyacrylamide polymers
(such as nonionic polyacrylamide polymers including substituted
branched or unbranched polymers and multi-block copolymers of
acrylamides and substituted acrylamides with acrylic acids and
substituted acrylic acids); polysaccharides (which refers to
gelling agents that contain a backbone of repeating sugar (i.e.,
carbohydrate) units, including cellulose, carboxymethyl
hydroxyethylcellulose, cellulose acetate propionate carboxylate,
hydroxyethylcellulose, hydroxyethyl ethylcellulose,
hydroxypropylcellulose, hydroxypropyl methylcellulose, methyl
hydroxyethylcellulose, microcrystalline cellulose, sodium cellulose
sulfate, and mixtures thereof); and gums (such as acacia, agar,
algin, alginic acid, ammonium alginate, amylopectin, calcium
alginate, calcium carrageenan, camitine, carrageenan, dextrin,
gelatin, gellan gum, guar gum, guar hydroxypropyltrimonium
chloride, hectorite, hyaluroinic acid, hydrated silica,
hydroxypropyl chitosan, hydroxypropyl guar, karaya gum, kelp,
locust bean gum, natto gum, potassium alginate, potassium
carrageenan, propylene glycol alginate, sclerotium gum, sodium
carboyxmethyl dextran, sodium carrageenan, tragacanth gum, xanthan
gum, and mixtures thereof).
Composition Preparation
[0184] The compositions useful for the methods of the present
invention are generally prepared by conventional methods such as
are known in the art of making topical compositions. Such methods
typically involve mixing of the ingredients in one or more steps to
a relatively uniform state, with or without heating, cooling,
application of vacuum, and the like.
Preservatives
[0185] Preservatives can be incorporated into the compositions of
the present invention to protect against the growth of potentially
harmful microorganisms. While it is in the aqueous phase that
microorganisms tend to grow, microorganisms can also reside in the
anhydrous or oil phase. As such, preservatives, which have
solubility in both water and oil, are preferably employed in the
present compositions. Suitable traditional preservatives for
compositions of this invention are alkyl esters of
parahydroxybenzoic acid. Other preservatives, which can be used
include hydantoin derivatives, propionate salts, and a variety of
quaternary ammonium compounds.
[0186] Particularly preferred preservatives are methylparaben,
imidazolidinyl urea, sodium dehydroacetate, propylparaben,
trisodium ethylenediamine tetraacetate (EDTA), and benzyl alcohol.
The preservative can be selected to avoid possible
incompatibilities between the preservative and other ingredients.
Preservatives are preferably employed in amounts ranging from about
0.01% to about 2% by weight of the composition. Other preservatives
known in the art can be used in the present invention.
Methods of Administration
[0187] Another aspect of the invention is to provide a method of
administering a composition of the invention, wherein dispersed
lipid vesicles and/or cyclodextrins comprising collagen are
provided to the dermal layer of a patient's skin. The method
includes the step of contacting the skin or other target site of
the subject with a composition including a lipid vesicle (e.g.,
non-phospholipid paucilamellar lipid vesicle) having a cavity
containing human collagen.
[0188] The compositions of the present invention are useful for
regulating and/or improving mammalian skin condition. Such
regulation of epidermal tissue conditions can include prophylactic
and therapeutic regulation. For example, such regulating methods
are directed to thickening dermal tissue and preventing and/or
retarding atrophy of mammalian skin, preventing and/or retarding
the appearance of spider vessels and/or red blotchiness on
mammalian skin, preventing and/or retarding the appearance of dark
circles under the eye of a mammal, preventing and/or retarding
sallowness of mammalian skin, preventing and/or retarding sagging
of mammalian skin, softening and/or smoothing lips of a mammal,
preventing and/or relieving itch of mammalian skin, regulating skin
texture (e.g. wrinkles and fine lines), and improving skin color
(e.g. redness, freckles).
[0189] Regulating epidermal tissue condition involves topically
applying to the epidermal tissue a safe and effective amount of a
composition of the present invention. The amount of the composition
which is applied, the frequency of application and the period of
use will vary widely depending upon the level of collagen (and,
when present, other skin care agents) of a given composition and
the level of regulation desired, e.g., in light of the level of
epidermal tissue damage present or expected to occur.
[0190] In a preferred embodiment, the composition is chronically
applied to the skin. By "chronic topical application" is meant
continued topical application of the composition over an extended
period during the subject's lifetime, preferably for a period of at
least about one week, more preferably for a period of at least
about one month, even more preferably for at least about three
months, even more preferably for at least about six months, and
more preferably still for at least about one year. While benefits
are obtainable after various maximum periods of use (e.g., five,
ten or twenty years), it is preferred that chronic application
continue throughout the subject's lifetime. Typically applications
would be on the order of about once per day over such extended
periods, however application rates can vary from about once per
week up to about three times per day or more.
[0191] A wide range of quantities of the compositions of the
present invention can be employed to provide a skin appearance
and/or feel benefit. Quantities of the present compositions which
are typically applied per application are, in mg
composition/cm.sup.2 skin, from about 0.1 mg/cm.sup.2 to about 10
mg/cm.sup.2. A particularly useful application amount is about 1
mg/cm.sup.2 to about 2 mg/cm.sup.2.
[0192] Improving and/or regulating epidermal tissue condition is
preferably practiced by applying a composition in the form of a
skin lotion, cream, gel, foam, ointment, paste, emulsion, spray,
conditioner, tonic, cosmetic, lipstick, foundation, after-shave, or
the like which is preferably intended to be left on the skin or
other keratin structure for some esthetic, prophylactic,
therapeutic or other benefit (i.e., a "leave-on" composition).
After applying the composition to the skin, it is preferably left
on the skin for a period of at least about 15 minutes, more
preferably at least about 30 minutes, even more preferably at least
about 1 hour, still more preferably for at least several hours,
e.g., up to about 12 hours. Any part of the external portion of the
body can be treated, e.g., lips, under-eye area, eyelids, scalp,
neck, torso, arms, hands, legs, feet, etc. The composition can be
applied with the fingers or with an implement or device (e.g., pad,
cotton ball, applicator pen, spray applicator, and the like).
[0193] Another approach to ensure a continuous dispersal of at
least a minimum level of collagen (and, when present, at least one
skin care agent) to the dermal layer is to apply the compound by
use of a patch applied, e.g., to the face. Such an approach is
particularly useful for problem skin areas needing more intensive
treatment (e.g., facial crows feet area, frown lines, under eye
area, and the like). The patch can be occlusive, semi-occlusive or
non-occlusive and can be adhesive or non-adhesive. The composition
can be contained within the patch or be applied to the skin prior
to application of the patch. The patch can also include additional
agents such as chemical initiators for exothermic reactions such as
those described in U.S. Pat. Nos. 5,821,250, 5,981,547, and
5,972,957 to Wu, et al. The patch is preferably left on the skin
for a period of at least about 5 minutes, more preferably at least
about 15 minutes, more preferably still at least about 30 minutes,
even more preferably at least about 1 hour, still more preferably
at night as a form of night therapy.
EXAMPLE 1
Absorption of Collagen into Skin
[0194] The study evaluated the percutaneous absorption
pharmacokinetics of .sup.14C-Collagen spiked to a liposome.
Absorption was measured in excised human face skin, in vitro, using
the finite dose technique and Franz Diffusion Cells.
[0195] The in vitro human cadaver skin model has proven to be a
valuable tool for the study of percutaneous absorption and the
determination of the pharmacokinetics of topically applied drugs.
The model uses human cadaver skin mounted in specially designed
diffuision cells that allow the skin to be maintained at a
temperature and humidity that match typical in vivo conditions. A
finite dose (e.g. 4-7 mg/cm.sup.2) of formulation is applied to the
outer surface of the skin and drug absorption is measured by
monitoring its rate of appearance in the receptor solution bathing
the inner surface of the skin. TABLE-US-00001 Test Article - Day
Cream Tracer - .sup.14C Collagen (ARC 2005) (methyl-14C)
[0196] The product was tested on replicate skin sections from three
different skin donors, for the percutaneous absorption of
.sup.14C-Collagen spiked formulation over a 48-hour dose period. At
pre-selected times after dosing, the dermal reservoir solution was
removed in its entirety, replaced with fresh receptor solution, and
an aliquot saved for subsequent analysis. At the completion of the
study, the dermal and epidermal contents were also evaluated. The
samples were analyzed for .sup.14C isotope content by liquid
scintillation spectroscopy. TABLE-US-00002 Summary Table:
[.sup.14C]-Collagen spiked Novasome Total Absorption Results Across
Donor Skin Source Total Pen* (.mu.g) Total Pen (%) Eyelid 3.83 .+-.
2.40 42.96 .+-. 21.21 Pre-Auricular 2.63 .+-. 0.56 19.63 .+-. 1.27
Combined Data 3.03 .+-. 0.51 27.40 .+-. 7.81 Percutaneous
Absorption of .sup.14C-Collagen as radioisotope through Excised
Human Face Skin over 48 hours from a Single Application. Mean .+-.
SE (n = 3) as Total Mass (.mu.g) and Percent of Applied Dose *"Pen"
is penetration
[0197] The radiolabeled collagen was prepared by American
Radiolabeled Chemicals, Inc. (ARC; St. Louis, Mo. 63143). Briefly,
the study Sponsor sent their collagen to ARC for labeling. ARC
labeled the collagen by methylation using [.sup.14C] formaldehyde
and sodium cyanoborohydride. The radiolabeled material was
indicated to have a specific activity of 25 .mu.Ci/mg and was
provided in a 1 mL volume of 0.01M potassium phosphate buffer (pH
7.2).
[0198] The radiolabeled material was first dried by vacuum
centrifugation (Speed Vac, Savant, Inc.) for approximately 3 hours,
followed by reconstitution in 50 .mu.L of the Novasome Day Cream
and mixed by dual syringe (100 .mu.L) cross extrusion through a
3-way stop-cock valve 20 times. The spiked cream was allowed to
equilibrate for 24 hrs at room temperature prior to use. Final
specific activity was measured as 0.1 .mu.Ci/.mu.L cream
formulation with 3.82 .mu.g/uL radiolabeled collagen contributing
to the cream base.
Study Skin Preparation:
[0199] Human excised face skin (eyelid and pre-auricular) without
obvious signs of skin disease, obtained following cosmetic surgery,
was used in this study. It was cleared of all subcutaneous tissue
and the lower .about.25% of the dermis, sealed in water-impermeable
plastic bags and stored at .ltoreq.-70.degree. C. until used. Prior
to the experiment, skin was thawed, and then rinsed in water to
remove any adherent blood or other material from the surface.
[0200] Skin from a single donor was cut into multiple smaller
sections large enough to fit on Franz diffusion cells (0.4
cm.sup.2-0.8 cm.sup.2). The dermal chamber was filled to capacity
with a reservoir solution of phosphate-buffered isotonic saline
(PBS), pH 7.4.+-.0.1, and the epidermal chamber was left open to
the ambient laboratory environment. The cells were then placed in a
diffusion apparatus in which the dermal reservoir solution was
stirred magnetically at approximately 600 RPM and its skin surface
temperature maintained at 32.0.degree..+-.1.0.degree. C.
[0201] To assure the integrity of each skin section, its
permeability to tritiated water was determined before application
of the test products. Following a brief (0.5-1 hour) equilibrium
period, .sup.3H.sub.2O (NEN, Boston, Mass., sp. Act. .about.0.5
.mu.Ci/mL) was layered across the top of the skin by dropper so
that the entire exposed surface was covered (approximately 100-500
.mu.L). After 5 minutes the .sup.3H.sub.2O aqueous layer was
removed. At 30 minutes the receptor solution was collected and
analyzed for radioactive content by liquid scintillation counting.
Following the integrity test the receptor solution was changed
multiple times to remove any measurable residual tritium.
Dosing and Sample Collection
[0202] Prior to administration of the topical test formulations to
the skin sections, the chimney was removed from the Franz Cell to
allow full access to the epidermal surface of the skin and the
reservoir solution was replaced with a fresh solution of PBS.
[0203] Subsequently, the test product was applied to replicate
sections of the same donor skin. Dosing was performed using a
positive displacement pipette set to deliver 5 .mu.L
formulations/cm.sup.2. Given the available skin, three chamber
sizes with different dosing area were using (0.4, 0.5 and 0.8
cm.sup.2). The dose was spread throughout the surface with the tip
of the pipette. Five to ten minutes after application the chimney
portion of the Franz Cell was replaced. Spare cells were not dosed,
but sampled, to evaluate for interfering substances during the
analytical analysis.
[0204] At pre-selected time intervals after test formulation
application (0.5, 1, 3, 7, 19, 26, 43, 48 hr) the receptor solution
was removed in its entirety replaced with fresh solution, and an
aliquot taken for analysis.
[0205] After the last sample was collected, the surface of the skin
was washed with double distilled de-ionized water to collect
un-absorbed formulation form the surface of the skin. Following the
wash, the skin was removed from the chamber, separated into
epidermis and dermis, and each processed for subsequent analysis
for isotope content.
Analytical Methods
[0206] Analysis for .sup.14C-isotope content of each sample was by
liquid scintillation spectroscopy. One-milliliter volumes of each
receptor solution and each surface wash solution received 5-7 mL
scintillation fluid. Tissue (epidermis and dermis) was dissolved in
Soluene-350 (PerkinElmer; Lot# 24-060203) overnight, following
which each sample received 5-7 mL of scintillation fluid.
[0207] Samples were quantified for .sup.14C content by liquid
scintillation spectroscopy using a PerkinElmer Tri-Carb 3100TR
liquid scintillation counter. Each sample was counted for no less
than 5 minutes each, in duplicate. Counts per minute (CPM) were
automatically converted to decays per minute (DPM) using the
external standard quench correction method. All data were corrected
for isotope background from blank samples. TABLE-US-00003 TABLE 1
Rate of Penetration as Mean Flux (.mu.g/cm.sup.2/hr) Results Time
(hr)* Eyelid Pre-Auricular Combined Data 0.25 0.14 .+-. 0.10 0.04
.+-. 0.02 0.07 .+-. 0.04 0.75 0.20 .+-. 0.02 0.12 .+-. 0.00 0.15
.+-. 0.03 2.0 0.18 .+-. 0.01 0.15 .+-. 0.06 0.16 .+-. 0.03 5.0 0.21
.+-. 0.09 0.10 .+-. 0.04 0.14 .+-. 0.04 13.0 0.17 .+-. 0.07 0.07
.+-. 0.01 0.11 .+-. 0.03 22.5 0.23 .+-. 0.18 0.08 .+-. 0.00 0.13
.+-. 0.05 35.0 0.10 .+-. 0.01 0.07 .+-. 0.00 0.08 .+-. 0.01 45.5
0.30 .+-. 0.30 0.07 .+-. 0.01 0.15 .+-. 0.08 Percutaneous
Absorption of .sup.14C-Collagen as radioisotope through Human
Cadaver Skin over 48 hours from a Single Application (Mean .+-. SD
Eyelid, Mean .+-. SE Pre-Auricular, n = 1-2 Donors). *Time as
midpoint between samples.
[0208] TABLE-US-00004 TABLE 2 Total Absorption and Mass Balance
Results Parameter Eyelid Pre-Auricular Combined Data Total
Absorption 3.83 .+-. 2.40 2.63 .+-. 0.56 3.03 .+-. 0.51 (.mu.g)
Dermis (.mu.g) 0.02 .+-. 0.01 0.03 .+-. 0.01 0.02 .+-. 0.01
Epidermis (.mu.g) 0.13 .+-. 0.06 0.28 .+-. 0.13 0.23 .+-. 0.09
Surface Wash (.mu.g) 5.37 .+-. 0.25 9.73 .+-. 1.65 8.28 .+-. 1.74
Total Absorption (5) 42.96 .+-. 21.21 19.63 .+-. 1.27 27.40 .+-.
7.81 Dermis (%) 0.20 .+-. 0.11 0.18 .+-. 0.03 0.19 .+-. 0.02
Epidermis (%) 1.51 .+-. 0.48 2.01 .+-. 0.66 1.84 .+-. 0.42 Surface
Wash (%) 63.14 .+-. 7.04 74.10 .+-. 0.48 70.45 .+-. 3.67 Total
Recovery (%) 107.81 .+-. 14.76 95.92 .+-. 2.44 99.88 .+-. 4.21
Percutaneous Absorption of .sup.14C-Collagen as radioisotope
through Human Cadaver Skin over 48 hours from a Single Application.
Mean .+-. SD Eyelid, and Mean .+-. SE Pre-Auricular as Percent of
Applied Dose and Total Mass (.mu.g). (n = 1-2 Donors)
[0209] The data indicated that when .sup.14C-Collagen is
incorporated into the Novasome Day Cream base formulation,
radioisotope penetrates into and through human excised face
skin.
[0210] It is to be understood that while the invention has been
described in conjunction with the detailed description thereof, the
foregoing description is intended to illustrate and not limit the
scope of the invention, which is defined by the scope of the
appended claims. Other aspects, advantages, and modifications are
within the scope of the following claims.
* * * * *