Specification
PROCESS FOR MAKING CONTROLLED RELEASE
MEDICAL IMPLANT PRODUCTS
Cross-Reference to Related Patents and Applications
This non-provisional application is based upon and claims domestic priority
benefits under 35 USC ยง 1 19(e) from copending U.S. provisional patent application Ser.
No. 61/709,856, filed on October 4, 2012, the entire contents of which are hereby
expressly incorporated herein by reference. The provisional patent application Ser. No.
61/709,856 and this non-provisional application based thereon are commonly owned by
Axxia Pharmaceuticals LLC ("Axxia").
Axxia also owns prior issued USP Nos. 5,633,000; 5,858,388; and 6,126,956 and
pending US Ser. Nos. 12/738,1 13; 61/533,131; 13/264,813; 13/606,795; and
2008/01 1908, the entire contents of each such prior-issue US patent and pending patent
application commonly owned by Axxia being expressly incorporated herein by reference
These Axxia prior patents and applications relate to controlled release medical implant
products and various non-3-D printing processes for making those products. According
to these Axxia prior patents and applications, the implants (i) may be non-biodegradable
or biodegradable; (ii) may provide drug delivery over a few days, weeks or months; (iii)
may provide a steady drug release without a "burst"; and (iv) may be in various sizes to
accommodate the desired drug delivery schedules. Significantly, none of these prior
Axxia patents or patent applications teach or suggest a 3-D printing method, let alone the
3-D printing method of this invention.
Field
This application sets forth novel 3-D printing processes for making subcutaneous
medical implant products that provide for the controlled release of non-narcotic as well as
opiate, opioid and/or other narcotic drugs over a period of days, weeks or months. These
novel processes can be used to make a wide variety of subcutaneous medical implant
products having self-contained controlled release drugs beyond those specifically
disclosed in Axxia's prior patents and applications. The present invention covers both
the 3-D printing processes described below and the products made by those processes.
Although the present invention is primarily described herein with respect to
medical implant products, the invention also is applicable with respect to medical nonimplant
products, such as tablets having time release capabilities and/or containing opioid
products. Thus, for example, the detailed description of the processes and products set
forth herein with respect to implants are readily adaptable to non-implant products as
would be readily understood by one of ordinary skill in the art after reading this
disclosure.
Further, the drug and non-drug materials in the present invention are not limited
to the materials disclosed in the Axxia patents and applications - e.g., there is no
limitation to the hydromorphone drug or to the EVA, TPU or silicone coating/matrix
materials. For example, the drug materials may be narcotics and/or non-narcotics.
Likewise, the non-drug materials may be biodegradable or non-biodegradable.
Thus, in addition to hydromorphone, this process also can be used to make the
probuphine implants of Titan Pharmaceuticals, the implants of Purdue Pharma and the
implants products of other companies. See, e.g., USP os. 8,1 14,383 and 8,309,060. In
other words, this application covers all subcutaneous medical implant products
containing controlled release drugs that are capable of being made by the invention.
The present processes and the products made by those processes are useful in at
least four fields of use: (1) the narcotic abuse field; (2) the drug compliance field (both
narcotic and non-narcotic drugs); (3) the pain management field; and (4) the animal heath
field.
Background
Inkjet and other printing processes have been used in many fields to manufacture
products. For example, inkjet printing processes have been used in the manufacture of
LCD and semiconductor products. See, e.g., Re. 37,682, which although it involves an
unrelated technical field is incorporated by reference herein in its entirety.
In addition, printing processes (such as screen printing and low temperature
casting techniques) have been the subject of consideration for the manufacture of other
medical (non-implant medical devices or non-self-containing drug implants) products.
See, e.g., "Printing Evolves: An Inkjet For Living Tissue," published in the Wall Street
Journal on September 18, 2012 at pages D and D3; and the Axxia patents/applications.
Further, non-printing methods have been used to create medical implant products,
via conventional methods. These non-printing methods include, inter alia, hot-melt
casting, extrusion, shrink-wrap and solvent based processes.
While some prior art processes have commercial advantages and they can be used
as a part of the invention herein, it is the inventors' opinion that these prior art processes
alone (i.e., when used without at least one 3-D printing process step) fail to satisfy at least
one or more of the advantages that the present 3-D printing invention seeks to provide for
controlled release subcutaneous medical implant devices and medical non-implant
products. For example, a partial listing of the advantages that may result from the present
3-D printing invention are believed to include at least some of the following:
1. The structure of the non-drug portions of the implant or nonimplant
product may be designed and controlled rather precisely
due to (i) the small, precise amounts of material deposited by each
3-D nozzle and (ii) the very thin or ultra-thin layer-by-layer
building method of 3-D printing; and
2. The drug release pattern of the implants or non-implants may be
precisely regulated by the use of the 3-D nozzles to create the
product on a layer-by-layer basis for the same reasons; and
3. The shape and configuration of the implant or non-implant may be
modified as desired by, for example, using the 3-D printing nozzles
to deposit non-permanent materials that may be readily removed
by etching, laser, mechanical, chemical or other known means; and
4. The present invention may avoid irregularities resulting from
cutting or otherwise modifying extruded materials; and
5. The present invention may sometimes avoid the separate step of
loading a drug material within the implant or non-implant because,
for example, the precise ratio of the drug material and the non-drug
material in the matrix core can be precisely regulated and the
release path and release rate of the drug materials within the matrix
core to the opening in the implant or non-implant device can be
precisely designed; and
6. The present invention may provide great flexibility in the choice
and use of both drug materials and non-drug materials, whereas,
for example, certain previously known processes limit the
commercial choice of plastic/thermoplastic/drug materials; and
7 . Large numbers of implants or non-implants may be created at one
time and/or quickly so that, e.g., the overall yield is increased; and
8 . The present invention may provide improved bonding/adhesion
between the drug containing matrix and other portions of the
implant or non-implant (e.g. the coating); and
9 . High manufacturing yield may be achieved - e.g., approaching as
high as about 90-95%. Thus, for example, with hydromorphone
costs of approximately $12,000/kg, this may be an important
competitive advantage, especially in developing world markets.
However, it should be understood that the present invention does not require that all of
these advantages be achieved in every process or product covered by the scope and spirit
of the invention.
Summary
In general, the present invention relates to computer-controlled 3-D printing
methods that are used (either wholly or in part) to manufacture controlled release medical
implant or non-implant products. One type of 3-D printing is sometimes referred to as
fused deposition modeling (FDM). This invention is not limited to any one type of 3-D
printing. Further, and indicated previously, this invention covers both implant and nonimplant
processes and products. For the purpose of providing a detailed description of
the invention, that description will focus upon implant processes and products. However,
those processes also are applicable to the manufacture of non-implant products as would
be readily understood by one of ordinary skill in the art after reviewing that description.
These subcutaneous implants provide for the controlled release of self-contained
drugs (whether they are narcotic or non-narcotic drugs) over at least a several week
period. In one embodiment of the invention, the controlled release time period is 30 days
or longer. However, the controlled release period may, in fact, also be a shorter period of
time, such as 3, 7, 14 or 2 1 days. Although a steady controlled release is frequently
desired, the release rate can be varied over time. In addition, more than one drug may be
released by an implant made in accordance with the invention.
The 3-D printing method may be accomplished via an array of 3-D nozzles that
deposit materials (such as plastics, thermoplastics, coating materials, drug-containing
matrix materials, non-drug containing matrix materials, bonding materials, biodegradable
materials and/or the like) in very small, precise portions. The materials may be deposited
in liquid, powder, sheet or other forms.
For example, the array of nozzles may be used to deposit one or more of these
materials on a thin or ultra-thin layer-by-layer basis to create/build the final controlled
release medical implant product. Although the 3-D nozzles may deposit the materials in
droplet form, the use of the nozzle array typically will result in a non-droplet shape at
each layer/slice. In one embodiment, there is a separate array of 3-D nozzles for at least
one portion of each layer.
However, the number of separate arrays of 3-D nozzles may be minimized so long
as the 3-D nozzles are capable of depositing more than one type of material at different
times during the process. Because this presently may be commercially impractical with
respect to some materials, it may not always be a preferred process feature. Nevertheless,
the scope of the invention cannot be avoided by this modification.
With respect to the manufacture of the Axxia products disclosed in its prior
patents and applications, the array of 3-D nozzles of this invention is capable of
depositing one or more types of materials during at least a portion of at least one layerby-
layer step in the product building process. The number of different types of materials
deposited by the array during any one layer deposition is dependent upon, inter alia, the
composition and the geometric design of the final product. Where more than one
material is deposited on a particular layer, the different materials may be deposited
simultaneously (either as a mixture or by separate nozzles) or sequentially.
If deposited sequentially, a portion of the previously deposited materials in that
layer may be removed prior to the subsequent deposition of other materials by techniques
such as etching, lasers or other means that are well known. This removal method may be
beneficial with respect to the deposition of drug materials and/or the creation of openings
in the implant product.
In addition, the removed portions may involve one or more layers of other
materials so that an open shell of coating materials may be created into which a drugcontaining
matrix core may be deposited via 3-D or other methods. In that situation, for
example, a drug-containing matrix core may be deposited layer-by-layer via 3-D printing
within the open shell of the outside coating structure prior to the deposition of the top
coating layer(s) of the implant product. In that situation, the matrix core may be created,
inter alia, by having one or more 3-D nozzles (i) deposit a mixture of the drug and nondrug
materials; (ii) separately deposit the drug and non-drug materials; or (iii) deposit
ultra-high pressure carbon dioxide as a part of the non-drug materials in order to create an
in situ foaming material that may enhance interconnective microporosity. The drug/nondrug
material may be mixed homogeneously or non-homogeneously.
Alternatively, instead of creating the matrix core within the open shell of coating
materials, the matrix core may be created separately and then mechanically or otherwise
inserted within the open shell.
Furthermore, the matrix core structure and/or its drug release pattern may be
enhanced (with respect to one or more of the layer-by-layer depositions) by first
depositing only the non-drug containing material, then removing portions of that material
and then depositing the drug containing material. In that circumstance, the matrix core
material and/or the opening material may be deposited sequentially. For example, one or
both of these materials may be deposited after another interim or temporary material has
been deposited and then removed. This approach has the potential advantage of more
precisely controlling the narcotic drug release pattern via micro-channels within the
matrix core and the opening in the implant device.
In yet another embodiment of the invention, a rapidly biodegradable material may
be used to form all or part of the opening in the implant device. This may have the
advantage of an improved hygienic product and/or to control the initial drug burst if, for
example, one wanted to begin drug release several days after implantation.
Similarly, a biodegradable material may be used to form all or part of the implant
which, for example, obviates the need to physically remove the spent implant. Further,
biodegradable material may be used to form all or part of the non-drug portion of the
core. This may serve to improve the control release of the drug materials from the core.
The present invention also contemplates a high-speed and cost-efficient 3-D
printing-based manufacturing process for building incremental components into finished
drug delivery implant platforms. This process involves multiple pass or sequential
deposition of the same or different functional materials including active pharmaceutical
ingredients wherein at least portions of some or all layers can be brought to a final
physical product state using ultraviolet (UV) radiation or using other means.
More specifically, this radiation may instantly cross link the functional layers
without the need for thermal assist, thereby allowing for high speed operations while
eliminating the possibility of thermal decomposition to the component materials. In that
regard, UV curing systems are small, portable, highly efficient and inexpensive compared
to thermal curing or drying ovens. UV cross linkable formulations are 100% solids
liquids going into the printing process. No solvent is necessarily required so there is no
need to incur the expense of recovering or burning such a process aide that ultimately
doesn't become part of or add any value the final product.
In addition, the present invention contemplates the situations where (a) the
process involves the use of a 3-D printing process alone or (b) in combination with (i) an
non-3-D inkjet process, (ii) a non-inkjet process, (iii) a combination of those two
processes or (iv) a combination of one or more of those processes with one or more other
non-printing processes (such as extrusion). For example, in the combination situation, it
may be preferable to use an inkjet printer process to deposit certain materials and to use a
non-inkjet printer process (or a non-printing process) to deposit other materials.
As indicated above, the present invention covers the situation where the 3-D
printing method is used to create all or only a portion of the controlled release medical
implant product. As a result, the invention contemplates the situation where one or more
layers or where one or more parts of layers are created by non-3-D methods. For
example, all or part of the matrix core may be created via 3-D printing with all or part of
the core, coating and/or opening created by other processes.
Further, it should be understood that the process may be used to deposit multiple
layers having the same or different thicknesses. In that regard, the dimensions of medical
implant devices can vary widely.
However, the implant device envisioned by this invention may be about the size
of a shirt button or smaller. Thus, very approximate dimensions are about 0.5 to 25 mm
in height and about 3 to 130 mm in length/diameter. Nevertheless, in the case of a large
patient (e.g., a horse), the dimensions in height and/or length/diameter may be much
larger. See, e.g., the discussion of the effects of these dimensions as set forth in the
aforesaid Axxia prior patents and patent applications.
In addition, 3-D printing may be used to create radio opaque markers (as very
generally described in Axxia prior patent application Ser. No. 2008/01 1908).
By utilizing the present 3-D invention, the thickness of an individual layer
deposited via a 3-D printing machine can be as thin as about 0.01mm or less. Examples
of commercially available industrial 3-D printing equipment and software can be readily
obtained via the Internet. See, for example, the websites of Stratasys, Organo Holdings,
3D Systems, Fortus, Daussault Systems, Autodesk and others.
The present invention is not limited to any specific 3-D printing machine or
software. In other words, there is no preferred 3-D equipment or software.
By way of example only and with respect to the only ultimate products disclosed
in the Axxia prior patents/applications identified above, the implant has an impermeable
outer coating that surrounds a drug/non-drug matrix core. After implantation, the drug
material is released on a controlled basis through one or more openings in the coating
material to the mammalian (human or animal) patient.
As a result, one layer of the present implant may contain only one type of material
(e.g., a coating material) as well as an opening. However, another layer of the present
implant may contain multiple types of material (e.g., coating, EVA or TPU, and drug
materials) as well as an opening.
In other words, the process of the present invention may be used to create not only
the core (the interior drug containing matrix material) of the implant described in the
Axxia patents/applications but also the openings and/or the micro-channels within the
core that in combination facilitate release of the drug from the matrix core into one or
more openings which lead to the exterior of the implant and from which the drug is
released.
It is believed that one potentially important feature of the present process may be
the creation of a strong or an improved bond (via chemical, mechanical and/or other
means) between the coating and the matrix core materials. Thus, for example, a separate
bonding material can be used between the outside coating material and the matrix core.
Alternatively, a very thin or ultra thin layer or portion of a layer composed of the
coating material and the non-drug containing matrix material may be formed via 3-D
printing (either simultaneously or sequentially). These materials can be separated
deposited via different nozzles or they can be deposited together as a mixture via the
nozzles. This may result in a strong or an improved bond.
Brief Description of the Drawings
FIG. 1 is a perspective view of an exemplary embodiment of a product made by
the process of the present invention. The size and dimensions of the product have been
exaggerated for illustrative purposes.
FIG. 2 is a cross-sectional view of the product in FIG. along line 2-2. The size
and dimensions of the product have been exaggerated for illustrative purposes.
FIGS. 3A, 3B, 3C, 3D and 3E illustrate in cross-sectional, partial views along line
2-2 some (but not necessarily all) of the processing steps required to fabricate the
products of FIGS. 1 and 2. Once again, the size and dimensions have been exaggerated
for illustrative purposes. In addition, the size, location and number of 3-D printing
nozzles have been exaggerated for illustrative purposes.
FIG. 4 illustrates the use of a mold (that can be reusable or not) to serve as the
boundary between individual implant devices. The dimensions of the mold in this
drawing also have been exaggerated for illustrative purposes.
FIG. 5 illustrates the creation of an implant where more than the core contains
more than one drug.
Detailed Description
The present invention covers a wide variety of 3-D printing processes that may be
used to create virtually any implant or non-implant device. Therefore, the selection and
description of a particular implant/non-implant device or a particular 3-D process for
illustrative purposes is not intended to limit the scope of the invention.
In that regard, the implant device in FIGS. 1 and 2 is prior art, see Axxia USP
6,126,956. That implant structure is used solely for illustrative purposes and it is not
intended to limit the scope of this invention because the invention covers any implant
device manufactured in whole or in part via a 3-D printing process.
Turning to FIG. 1, an abuse deterrent, subcutaneous implant 2 permits the
controlled release of self-contained drug materials. A self-contained drug implant means
that all of the drug materials are within the implant prior to being implanted into the
patient. The phrase is intended to distinguish medical devices (such as a pump) wherein
additional drugs are introduced into the patient via the device after the device has been
implanted into the patient.
Implant 2 typically will have a top 4, a bottom 6 and an outside wall 8 . Although
FIG. 1 illustrates implant 2 in a button-like or cylindrical shape, virtually any geometric
shape can be constructed, if desired. An opening 10 permits the controlled release of the
drug - whether a narcotic or non-narcotic drug.
Although FIG. 1 shows one opening 10, it also is possible that one or more
openings could be used with respect to an implant containing more than one drug having
different release rates. Typically, however, one opening can be used with respect to the
release of more than one drug. See FIG. 5 discussed below.
In addition, all or part of opening 10 may contain removable materials. For
example, the opening may contain rapidly biodegradable substances so that the opening
is not complete until after insertion into the human or animal at which time this rapidly
biodegradable material will be absorbed or will otherwise disappear in the human or
animal. Examples of such a rapidly biodegradable material include, inter alia,
"Biodegradable Polymer Implants to Treat Brain Tumors," Journal of Controlled Release
74 (2001) 63-67; and "An Introduction to Biodegradable Polymers as Implant Materials,"
White Paper from Inion OY (2005).
If a rapidly biodegradable material is used to create temporary plugs at the
portions of the opening 16 at and near the top and the bottom of implant 2 it may be
desirable to fill the remainder of the opening with a different rapidly biodegradable
material, such as water or saline. In that situation, the plug portion of the rapidly
biodegradable material may be selected from suitable materials so that the plug will
rapidly degrade after implantation - but not during normal production, transportation or
handling.
Of course, alternatively the opening may be filled with non-biodegradable
materials in during the 3-D manufacturing process so long those materials are removed
prior to being implanted in the patient.
FIG. 2, shows the cross-sectional view of the product in FIG. 1 along line 2-2.
The top, bottom and side walls create an impermeable coating 12. Within coating 12, is a
controlled release matrix core 14 containing both drug and non-drug material. By virtue
of 3-D printing the structure of this matrix core and its release pattern may be controlled
very precisely. Matrix core 14 has an uncoated wall 16 within implant 2 that abuts
opening 10 in order to permit the desired controlled release of the drug to the patient.
Coating 12 may be made up of one or more materials. Some examples of coating
materials include, but are not limited to, polymers, plastics, thermoplastics, EVA, TPU
and silicone.
Coating 12 should be impermeable in at least two ways. First, it must be
impermeable in terms of prohibiting the flow of the drug material from the matrix core 14
other than via designed openings.
Second, it must be impermeable in the sense that it has a high breaking strength.
USP 8,1 14,383 indicates that the breaking strength should be at least 500 N. However, it
is believed that a lower breaking strength (such as about 250 N) is still sufficiently high
so as to be commercially acceptable.
In addition, the present invention also contemplates the optional use of a bonding
material between coating 12 and matrix core 14. These bonding materials are well
known and they are preferably chosen on the basis of the coating and core materials.
If the coating and non-drug matrix core materials consist of EVA, TPU and/or
silicone, any suitable materials may be selected. Further, the bonding material may be
created from a mixture of the coating material and the matrix core material.
If the bonding material is sufficiently impermeable, then coating 12 need not be
impermeable.
As described above, matrix core 14 contains both a drug and non-drug material.
In the drug abuse field, the drug will involve a narcotic. See, USP 8,1 14,383, col. 2, 1. 45
to col. 5, 1. 32 for a partial listing of narcotic drugs.
In the drug compliance, pain management and animal health fields, the drug may
be narcotic and/or non-narcotic.
The currently preferred process involves the use of just 3-D printing methods (but
it does not exclude the use of some non-3-D printing steps). Thus, FIGS. 3A to 3E
illustrate only a 3-D printer process for the manufacture of medical implant devices.
FIG. 3A illustrates the first step in the preferred embodiment of the 3-D printing
process. In this preferred embodiment, the entire implant 2 is built solely via 3-D
printing. However, as described above, the present invention only requires that at least a
portion of one layer of the implant device be made via 3-D printing. Thus, the invention
covers the use of a 3-D printing process with other processes for making an implant.
Stage 10 is the product building platform upon which the medical implant 2
device will be built via a very thin or ultra thin layer-by-layer 3-D printing deposition
process. As currently envisioned, there will be at least three layer-by-layer depositions.
Stage 10 may be stationary. If stage 10 is stationary, then one 3-D process design
involves the use of multiple arrays of nozzles for the layer-by-layer deposition of
materials. In that situation, the stationary product building stage 10 utilizes multiple
movable arrays of nozzles capable of depositing each layer or a portion of each layer.
Thus, each separate array of nozzles can be designed to deposit one or more layers of
materials for building the implant device.
Although it is conceivable that a single array of nozzles can be used to deposit
different materials via one or more of the nozzles in that single array, it is presently
contemplated that the use of multiple arrays of nozzles will be more commercially
acceptable in terms, for example, of the potential problems that may arise where more
than one material is deposited by an individual nozzle at various layer steps of the layerby-
layer building process.
Currently, a non-stationary stage 10 is preferred. In that situation, the product may
be built layer-by-layer by moving it along a path having more than one array of nozzles.
This product building path may consist of one chamber or more than one chamber.
To ensure a high degree of product purity, the use of multiple "clean" chambers
may be desirable. Thus, for example, a separate chamber may be desired for (a) the
layer-by-layer construction of the bottom coating/opening/coating layer, (b) the layer-bylayer
construction of the coating/core/opening/core/coating layer and (c) the layer-bylayer
construction of the top coating/opening/coating layer.
Further, separate chambers may be desirable with respect to the optional bonding
layers between (i) the top layer of the bottom coating and the bottom layer of the matrix
core and (ii) the bottom layer of the top coating and the top layer of the matrix core. See
FIGS. 3B and 3D.
FIG. 3A also illustrates a bottom coating layer 12 of the implant 2 device being
deposited on stage 10. Bottom coating layer 12 contains one or more impermeable
coating materials 14. In addition, this layer contains an opening 16 or opening materials
(that will later be removed in whole or in part to create an opening during manufacture).
In the preferred embodiment, bottom coating layer 12 is created via an array of 3-D
printing nozzles 18, only some of which are illustrated in FIG. 3A.
As indicated above, the size of the controlled release medical implant 2 can vary.
For example, the implants may be the size of a shirt button or smaller. However, the
implants may be larger, depending upon the particular application, the desired controlled
release rate and/or the size of the patient (e.g., a large horse).
The use of a 3-D printing method permits a considerable variation in the thickness
of the materials being deposited on a specific layer and it also permits considerable
variation in thickness of the various layers being deposited. Thus, for example, on the
very first layer-by-layer deposition shown in FIG. 3A, bottom coating layer 12 has one
thickness and opening 16 has no thickness.
Similarly, bottom coating layer 12 can be built in one or more layer-by-layer
depositions. If there is more than one such deposition, the depositions may be of the
same or different thicknesses. If more than one layer is deposited, then the choice of
coating materials and their composition % may vary.
FIG. 3B illustrates the situation where one or more layers of coating 12 have been
deposited so that the desired thickness of the coating material has been achieved. FIG.
3B also illustrates the next different process step wherein an optional bonding layer 20 is
deposited.
Although bonding layer 20 may be a single material that is different from the
coating material 12 or the matrix core material 22, FIG. 3 illustrates the situation, where
the bonding layer is composed of the coating material and the matrix core material. More
specifically, in this preferred embodiment, the bonding material is a mixture of the
coating material 14 and the non-drug matrix core material 22. FIG. 3B shows this
mixture being deposited simultaneously via 3-D printer nozzles. However, it also is
contemplated that the nozzles 18 may deposit the coating and matrix core materials
separately (either at the same time or sequentially).
Alternatively, the bonding material may be composed, in whole or in part, of
different materials so long as the bonding material ensures sufficient adhesion between
the coating materials 14 and the matrix core materials 20.
As with all of the layers in this process, the thickness of the bonding material
layer may be varied depending upon the design requirements of the implant 2 device.
FIG. 3B illustrates the deposition of only one layer of bonding materials. However, more
than one layer may be utilized. If more than one layer is deposited, then the choice of
bonding materials and their composition % may vary.
FIG. 3C illustrates the deposition of the first layer of the matrix core 24. The
matrix core 22 is made from the matrix core materials 22 that are selected when
designing the composition and structure of the implant 2 . In the preferred embodiment,
the matrix core materials 24 are deposited via 3-D nozzles 18 in the form of a mixture of
drug and non-drug materials (as, for example, described in the mixture of materials
disclosed in Axxia's prior patents and applications). The particular % composition of this
mixture can be varied to meet the desired specifications for the implant 2 . Further, these
materials may be deposited homogenously or non-homogeneously depending upon the
design of the desired micro-channels.
However, it also is envisioned that the drug and non-drug materials forming the
matrix core may be deposited separately via nozzles 18 that deposit only one of these
materials. The overall matrix core structure of such a deposition process is believed to
provide potentially enhanced drug release profiles because specifically defined microchannels
can be designed via such a deposition process.
FIG. 3C also shows optional bonding layer 20.
FIG. 3D illustrates the situation where one or more layers matrix core materials
20 have been deposited so that the desired thickness of the matrix core 22 has been
achieved. FIG. 3D also illustrates the next different process step wherein another
optional bonding layer 20 is deposited. The comments with respect to FIG. 3B are
generally applicable here.
FIG. 3D shows where optional bonding layer 20 is being deposited via 3-D printer
nozzles. As a result, optional bonding layer 20 surrounds the matrix core 22. If more
than one layer is deposited, then the choice of bonding materials and their composition %
may vary.
FIG. 3E illustrates the situation where one or more layers of coating material 14
have been deposited via a 3-D printing process so as to create the top portion of coating
layer 12. If more than one layer is deposited, then the choice of coating materials and
their composition % may vary.
As discussed above, the preferred embodiment creates an opening 16 during the
manufacture of implant device 2 . However, the present invention also contemplates the
situation where materials are inserted into opening 16 on an interim or temporary basis
during the 3-D manufacturing process. However, as explained herein, these materials
will typically be entirely removed prior to implanting the device into the patient.
Thus, with respect to non-biodegradable materials, al of those materials should
be removed prior to implanting via well known means such as etching, mechanical means
(such as perforation or drilling), chemical means, lasers or the like. At the present time, it
is the inventors' opinion that chemical means appear to be the least commercially viable
because they may have the potential effect of interfering with the drug materials in the
matrix core 22 and/or of interfering with the controlled drug release.
Alternatively, rapidly biodegradable materials may be utilized within the opening.
These materials may be entirely removed via the means set forth above.
However, it also is envisioned that a small portion of the rapidly biodegradable
materials may be left within the opening 16 so that this portion will quickly disappear
after being implanted in the patient. The remaining rapidly biodegradable material may
be in the form of a thin plug at the ends of the opening and/or a thin coating along the
sidewalls of the opening.
In another embodiment of the invention, the outside shape of the medical implants
or non-implants can be constructed by having each layer created within an existing
outside mold or the like. This may be beneficial with respect to spherical, non-cylindrical
and/or non-flat shapes.
FIG. 4 illustrates a situation where an outside mold 26 may be utilized to enhance
the rapid production of large numbers of implants. In one example of a mold 26, a matrix
mold has curved mold walls 28 that assist in building large numbers of implants.
In this preferred embodiment the mold is re-usable and an individual implant
device 2 is created within the separate walls 28 of mold 26. The walls of mold 26 may be
designed so that they create the appropriate shape for the implants. In addition, the walls
28 may be coating with an appropriate material so that, upon removal from stage 10, the
implants are easily removed from the mold (e.g., by gravity).
Alternatively, the mold may be non-reusable. For example, a thin mold wall may
be created so that it becomes a part of the implants being manufactured. Then, after 3-D
processing is complete, the individual implants may separated from each other at the by
using laser or other cutting means to remove all or part of the mold.
In that situation, mold 26 may be created prior to the 3-D printing process. On the
other hand, it also is envisioned the nozzles 18 can be used to create/build such a nonreusable
mold during the implant manufacturing process.
Thus, it is contemplated that, as with semiconductor manufacturing where large
numbers of individual semiconductors are created at one time during processing, implants
12 may be created in very large numbers by the present invention. Subsequently, as
described above, the individual implants may be separated by mechanical means (e.g.,
cutting via lasers or blade mechanisms) or by other means (e.g., via chemical etching or
otherwise removing the undesired portions). Also, as described above, reusable or nonreusable
matrices may be used to create large numbers of implants.
Although the preferred embodiment in FIGS. 3 do not utilize any non-3-D
printing steps, the present invention does not mandate that only 3-D printing steps are
used to make the medical implant or non-implant devices. Instead, it only requires that a
3-D printing process is used to make at least a portion of one or more layers of the
devices.
An example of this includes the situation where a sheet of the coating layer
material 14 is laid upon a stage 10. See FIG. 3A. This coating material may be part or
all of bottom coating layer 12. Thereafter, the implant device 12 is generally built in
accordance with FIGS. 3B to 3E. Thus, where many implants are built upon this sheet of
material, the individual implants may be separated from each other via laser or other
means. Similarly, the openings may be created either via (a) laser or other means or (b)
non-deposition in the openings area when practicing the invention.
Another example is where the matrix core material is made in whole or in part via
3-D printing. This matrix core can be embedded with a coating layer made by any
number of means such as 3-D printing, extrusion, shrink wrap, spray et cetera.
Thereafter, an opening may be created by any of the means described herein or otherwise
known to one of ordinary skill in the art.
In addition, it should be understood that the materials in any particular layer (e.g.,
the coating and matrix core layers) may vary within that layer due to the thin and very
thin nature of the 3-D printing method.
Moreover, as mentioned above, the implant may contain more than one drug.
FIG. 5 illustrates one example of such an implant. This embodiment shows a "double
decker" implant design. Implant 2 has a coating 12 that essentially surrounds two cores
14. Implant 2 also has an opening 19 with uncoated walls 16. In this embodiment,
different drug materials 30, 32 are contained in the two cores 14. Of course, it is possible
to have more than just two drugs within the implant by, for example, have more than two
cores.
As may be readily appreciated by those of skill in the manufacture of medical
implant or non-implant device art, the present invention can be practiced other than as is
specifically disclosed herein. Thus, while the invention has been described generally and
with respect to certain preferred embodiments, it is to be understood that the foregoing
and other modifications and variations may be made without departing from the scope or
the spirit of the invention.
We Claim :
1. A multi-step method of making a mammalian subcutaneous medical implant for
releasing self-contained drugs on a controlled basis over at least a 3 day period wherein
the method comprises depositing at least portions of one or more individual layers of the
implant by at least one computer controlled 3-D printer.
2 . A method according to claim 1, wherein the step of depositing portions of one or
more individual layers of the implant is practiced such that the implant comprises at least
(i) one coating, (ii) one drug-containing core and (iii) one opening.
3. A method according to claim 2, wherein the implant includes a binding material
to enhance adhesion between the coating and core and where the method includes
depositing at least a portion of the binding material by a 3-D printer.
4 . A method according to claim 3, wherein the coating or optional binding material
creates an impermeable layer so that the controlled release of the self-contained drug
materials is limited to one or more openings.
5 . A method according to claim 1, wherein at least a portion of the 3-D printing
method is performed within an enclosed chamber.
6. A method according to claim 1, wherein the implant is formed, at least in part, by
the use of more than one 3-D printers each having a multiple nozzle array.
7. A method according to claim 6, wherein the 3-D printer nozzle arrays deposit
more than one type of material during formation of at least one layer of the implant.
8. A method according to claim 6, wherein at least a part of one of the printer nozzle
arrays is capable of depositing more than one type of material to form the implant.
9. A method according to claim 1. wherein at least a portion of one or more layers
are removed.
0 . A method according to claim 1, wherein the steps include at least one 3-D
printing step and at least one non-3-D printing step.
11. A method according to claim 1 wherein at least a portion of one layer of the
matrix core is created by 3-D printing.
1 . A method according to claim 1, wherein the first step in the process is to supply a
sheet of prefabricated coating material.
13. A method according to claim 1, wherein at least one of the individual 3-D printer
layers is thicker than about 0.01 mm.
14. A method according to claim 1, wherein a matrix core layer is created, in whole
or in part, within a separate chamber.
15. A method according to claim 6, wherein at least one 3-D nozzle print array is
stationary.
16. A method according to claim 6, wherein at least one 3-D nozzle printer array is
non-stationary.
17. A method according to claim 2, wherein the opening is created at least in part
during a 3-D printing step.
18. A method according to claim 18, wherein the opening is created at least partially
from rapidly biodegradable materials.
19. A method according to claim 1, wherein at least one layer is formed with two or
more materials.
20. A method according to claim , wherein more than one implants are formed at the
same time and where one or more layers of each of the implants are created at least in
part by 3-D printing.
2 1. A method according to claim 20, wherein at least one process step involves at
separation of more than one implants at least in part by cutting, lasers, etching or
mechanical devices.
22. A method according to claim 21, wherein the separation step results in the
creation of a large number of individual implants to increase yield or to reduce
manufacturing expense.
23. A method according to claim 1, wherein at least three individual layers are created
by a 3-D printing process step.
24. A method according to claim 1, wherein the implant contains a radio opaque
marker and at least a portion of the marker is made by 3-D printing.
25. A subcutaneous medical implant for releasing self-contained drugs on a controlled
basis over at least a 3 day period wherein its method of manufacture involves, at least in
part, the use of at least one computer controlled 3-D printer to deposit portions of one or
more individual layers of the implant.
26. An implant according to claim 25, wherein at least a portion of the 3-D printing
method of manufacture is performed within an enclosed chamber.
27. An implant according to claim 25, wherein the implant is formed, at least in part,
by the use of more than one 3-D printers each having a multiple nozzle array.
28. An implant according to claim 27, wherein the 3-D printer nozzle arrays deposit
more than one type of material during formation of at least one layer of the implant.
29. An implant according to claim 27, wherein at least a part of one of the printer
nozzle arrays is capable of depositing more than one type of material to form the implant.
30. An implant according to claim 25, wherein at least a portion of one or more layers
are removed.
31. An implant according to claim 25, wherein the process steps include at least one
3-D printing step and at least one non-3-D printing step.
32. An implant according to claim 25 wherein at least a portion of one layer of the
matrix core is created by 3-D printing.
33. An implant according to claim 25, wherein at least one layer of the implant is a
sheet of prefabricated coating material.
34. An implant according to claim 26, wherein an opening is created at least in part
during a 3-D printing step.
35. An implant according to claim 25, wherein at least one layer of the implant is
formed with two or more materials.
36. An implant according to claim 25, wherein more than one implants are formed at
the same time and where one or more layers of each of the implants are created at least in
part by 3-D printing.
37. An implant according to claim 36, wherein separation of the implants involves
cutting, lasers, etching or mechanical devices.
38. An implant according to claim 37, wherein the separation results in the creation of
a large number of individual implants to increase yield or to reduce manufacturing
expense.
39. An implant according to claim 25, wherein at least three individual layers of the
implant are created by a 3-D printing process step.
40. A multi-step method of making a mammalian medical non-implant product for
releasing self-contained drugs on a controlled basis over at least a 12 hour time period
wherein the method comprises depositing at least portions of one or more individual
layers of the product by at least one computer controlled 3-D printer.
4 1. A medical non-implant product for releasing self-contained drugs on a controlled
basis over at least a 12 hour time period wherein its method of manufacture involves, at
least in part, the use of at least one computer controlled 3-D printer to deposit portions of
one or more individual layers of the product.
