Patent Application
20120017609
This invention relates, in general, to biopharmaceutical materials, preservation methods and systems, and more particularly to systems and methods for freezing, mixing, storing and thawing of biopharmaceutical materials.
Preservation of biopharmaceutical materials, such as cryopreservation, is important in the manufacture, use, transport, storage and sale of such materials. For example, biopharmaceutical materials are often preserved by freezing between processing steps and during storage. Similarly, biopharmaceutical materials are often frozen and thawed as part of the development process to enhance the quality or to simplify the development process.
When freezing biopharmaceutical materials, the overall quality, and in particular pharmaceutical activity, of the biopharmaceutical materials is desirably preserved, without substantial degradation of the biopharmaceutical materials.
Currently, preservation of biopharmaceutical material, particularly in bulk quantities, often involves placing a container containing liquid biopharmaceutical material in a cabinet freezer, chest freezer or walk-in freezer and allowing the biopharmaceutical material to freeze. Specifically, the container, which is typically one or more liters in volume and may range up to ten or more liters, is often placed on a shelf in the cabinet freezer, chest freezer or walk-in freezer and the biopharmaceutical material is allowed to freeze. These containers may be stainless-steel vessels, plastic bottles or carboys, or plastic bags. They are typically filled with a specified volume to allow for freezing and expansion and then transferred into the freezers at temperatures typically ranging from negative 20 degrees Celsius to negative 70 degrees Celsius or below.
To ensure efficient use of available space inside the freezer, containers are placed alongside one another and sometimes are stacked into an array with varied spatial regularity. Under these conditions, cooling of the biopharmaceutical solution occurs at different rates depending on the exposure of each container to the surrounding cold air, and the extent to which that container is shielded by neighboring containers. For example, containers placed close to the cooling source or those on the outside of an array of containers would be cooled more rapidly than those further away from the cooling source and/or situated at the interior of the array.
In general, adjacent placement of multiple containers in a freezer creates thermal gradients from container to container. The freezing rate and product quality then depend on the actual freezer load, space between the containers, container size, container shape, and air movement in the freezer. This results in a different thermal history for the contents of the containers depending on their location in a freezer, and their size, for example. Also, the use of different containers for individual portions of a single batch of biopharmaceutical material may cause different results for portions of the same batch due to different thermal histories resulting from freezing in a multiple container freezer, particularly if the storage arrangement, and/or the size and shape of the containers, is haphazard and random. Another consequence of obtaining a range of freezing times is that the contents of certain containers may freeze so slowly that the target solute can no longer be captured within the ice phase, but remains in a progressively smaller liquid phase. This phenomenon is referred to as cyroconcentration. In some cases such cyroconcentration could result in precipitation of the biopharmaceutical product, thus resulting in product loss.
Disposable bulk storage containers such as plastic bags or other flexible containers often are damaged, leading to loss of the biopharmaceutical material. Particularly, the volumetric expansion of the biopharmaceutical materials during freezing could generate excessive pressure in an over filled bag or in a pocket of occluded liquid adjoining the bag material, possibly leading to rupture or damage to the integrity of the bag. Moreover, handling of such disposable containers, such as plastic bags, during freezing, thawing, or transportation of these containers often result in damage thereof, due, for example, to shock, abrasion, impact, or other mishandling events arising from operator errors or inadequate protection of the bags in use.
Similarly, thawing of bulk biopharmaceutical materials typically involved removing them from a freezer and allowing them to thaw at room temperature. Such uncontrolled thawing can also lead to product loss. Generally, rapid thawing of biopharmaceutical materials results in less product loss than slower thawing. Further, it may also be desirable to control temperature of the biopharmaceutical materials during a thawing process since exposure of some biopharmaceutical materials to elevated temperatures may also lead to product loss. For example, it may be desirable to maintain a thawing biopharmaceutical material at about 0° C. when still in liquid and solid form during thawing thereof.
Further, it may be desirable to mix liquid bulk biopharmaceutical material at a homogeneous temperature above, below, or at an ambient temperature level. The mixing of biopharmaceutical materials in containers is important in the manufacture, use, transport, and storage of such materials. For example, biopharmaceutical materials are often blended, compounded, or formulated by mixing during processing steps and kept homogeneous during storage. Similarly, biopharmaceutical materials are often blended, compounded, or formulated by mixing as part of this development process to enhance the quality or to simplify the development process.
Currently, in some aspects, mixing of bulk biopharmaceutical materials involves transferring the product out of a container comprising the biopharmaceutical materials into a tank with a mechanical agitator, mixing and transferring the material back to the container. During those operations the containment may be broken and the product sterility and purity compromised. The homogeneous product may separate again after transfer back to its original container. Multiple transfers may expose product to excessive shear and to gas-liquid interfaces, which may adversely affect the product. Thus, it is preferable if such mixing can be accomplished without transferring the biopharmaceutical material out of the container or inserting a mixer into the container, i.e., noninvasive mixing is preferred. When utilizing such noninvasive mixing, the overall quality, sterility, and in particular pharmaceutical activity, of the biopharmaceutical materials is desirably preserved, without substantial degradation of the biopharmaceutical materials.
Thus, there is a need for systems and methods for freezing, thawing, storing, and mixing biopharmaceutical materials, particularly in bulk quantities, that are controlled, do not result in loss of biopharmaceutical material, and are repeatable.
The present invention provides, in a first aspect, a system for use in freezing, storing and thawing biopharmaceutical materials which includes a flexible sterile container means for holding biopharmaceutical material therein and a holder more rigid than said container means. The container means is received in a cavity of the holder and the holder extends along a perimeter of the container means. The holder is fixedly connected to the container means. The holder includes opposing sides defining an opening and the container means extends between the opposing sides of the holder defining the opening. The container means includes a substantially smooth exterior surface extending between the opposing sides.
The present invention provides, in a second aspect, a method for use in freezing, storing and thawing biopharmaceutical materials which includes providing a flexible sterile container means for holding biopharmaceutical material therein. The holder is more rigid than the container means and is fixedly connected to the container means. The container means is received in a cavity of the holder and the holder extends along a perimeter of the container means. The container means extends between opposing sides of the holder defining an opening. The container means includes a substantially smooth exterior surface extending between the opposing sides.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention will be readily understood from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawings in which:
In accordance with the principles of the present invention, systems and methods for freezing, thawing and storing biopharmaceutical materials are provided.
In an exemplary embodiment depicted in
Flexible container 10 (
Container 10 may be adapted to receive and contain frozen and/or liquid biopharmaceutical materials. In an embodiment, the biopharmaceutical materials may comprise protein solutions, protein formulations, amino acid solutions, amino acid formulations, peptide solutions, peptide formulations, DNA solutions, DNA formulations, RNA solutions, RNA formulations, nucleic acid solutions, nucleic acid formulations, antibodies and their fragments, enzymes and their fragments, vaccines, viruses and their fragments, biological cell suspensions, biological cell fragment suspensions (including cell organelles, nuclei, inclusion bodies, membrane proteins, and/or membranes), tissue fragments suspensions, cell aggregates suspensions, biological tissues in solution, organs in solution, embryos in solution, cell growth media, serum, biologicals, blood products, preservation solutions, fermentation broths, and cell culture fluids with and without cells, mixtures of the above and biocatalysts and their fragments.
Sterile, flexible container 10 may be configured (e.g., shaped and dimensioned) to be received in, and integrally connected to, a supporting structure, such as frame or holder 15 (
The openings (e.g., first opening 210 and second opening 211) in holder 15 may extend between opposite sides of a restraining flange or rim 246 of holder 15, which is configured to provide support to container 10 when it is filled with biopharmaceutical materials. More specifically, each opening may be surrounded by such a rim or other interior portion of a holder. Further, rim 246 may provide support in a direction such that it retains the container in the cavity (e.g., rim 246 may abut an exterior surface of container 10 and may inhibit movement of container 10 through opening 210 or opening 211 toward an exterior of holder 15). Also, rim 246 is shaped to retain and protect an outer perimeter of container 10, e.g., to inhibit or prevent sharp edges from contacting the container. Further, container 10 may extend substantially flat or smooth between opposite sides of rim 246. Also, the openings expose a large surface area of container 10 to an exterior of holder 15. For example, container 10 may be exposed to an interior 26 of a temperature control unit 20 (
As depicted in
As shown in
Conduit 120 may be integral to container 10 or it may be connectable to a receiving port (not shown) thereof. For example, conduit 120 could be connected to a receiving port using a fitting placed within the inlet port. Fittings such as those described in U.S. Pat. No. 6,186,932, may be used for the connection of such conduits. Also, fittings which can maintain the sterility of the contents of the container or flexible container may preferably be used. The fittings may be configured in different shapes, such as straight fittings and/or angled fittings including ninety (90) degree elbows, if desired. In another example, conduit 120 may include a filter (not shown) to filter any impurities or other undesirable materials from the biopharmaceutical material. Storage cavity 222 may protect conduit 120 and the fittings from any damage resulting from impact or stress such as the impact resulting from a person dropping holder 15 when container 10 is filled with biopharmaceutical materials.
Holder 15 may preferably be formed of materials which remain stable and retain their structural properties over a large range of temperatures. Specifically, such materials should retain their load-bearing capacity and exhibit cold crack temperatures no higher than negative 80 degrees Celsius while being resistant to cleaning agents and methods commonly used in biopharmaceutical manufacturing, e.g., sodium hydroxide, sodium hypochloride (e.g., CLOROX), peracetic acid, etc. For example, holder 15 could be formed of injection molded plastic or thermo formed plastic. Also, holder 15 may be formed of fluoropolymer resin (e.g. TEFLON), stainless steel or any number of other materials including aluminum, polyethylene, polypropylene, polycarbonate, and polysulfone, for example. Further materials may include composite materials such as glass-reinforced plastic, carbon-fiber reinforced resins, or other engineering plastic materials known to offer high strength-to-weight rations and which are serviceable at various temperatures of interest. It will be understood by those skilled in the art that first portion 115 and second portion 117 may be monolithic and integrally formed as one piece or fixedly connected together. Further, holder 15 could be formed of a single material (e.g., injection molded plastic) or it could be formed of different materials and connected together. Also, such holders (e.g., holder 15) integrally connected to flexible containers (e.g., containers 10 and 410) may be disposable, thus promoting ease of use.
Also, a holder (e.g., holder 15) may be formed, sized and/or dimensioned to receive and support containers of various sizes to provide additional rigidity and support to the container(s), thus facilitating handling, storage, and/or temperature control thereof. For example, as depicted in
In another example depicted in
Temperature control unit 20 is configured to control the temperature of cavity or interior 26 thereof, which may include one or more slots 25 as depicted in
In one embodiment, temperature control unit 20 includes a heat exchanger having one or more heat transfer or conduction plates for heating and/or cooling one or more containers and biopharmaceutical materials contained therein, as best depicted in
One or more of plates 28 could have heat transfer fluids circulating therethrough, such as water, oil, glycol, silicone fluid, hot air, cold air, alcohol, freons, freezing salty brines, liquid nitrogen or other heat transfer fluids as is known by those skilled in the art. Plates 28 could further include heat transfer enhancing structures such as fins and pins due to required high heat flux for product thawing, as will be understood by those skilled in the art.
One or more plates 28 may also include temperature sensor 18 mounted on an interior portion or exterior portion of plates 28 or it may be integral thereto. Temperature sensor 18 may detect a temperature of one or more of plates 28 and one or more locations thereon. Controller portion 21 of temperature control unit 20 may be coupled to temperature sensor 18 and to a heat transfer fluid control portion 22 of temperature control unit 20. Such heat transfer fluids may be circulated through plates 28 by heat transfer fluid control portion 22 controlled by controller portion 21 in response to temperatures detected by temperature sensor 18.
In another example, a temperature sensor (not shown) could be located in a heat transfer fluid input (not shown) of a plate and/or a heat transfer output (not shown) of such a plate. A difference between the temperatures determined at such points could be utilized to determine the temperature of the biopharmaceutical materials held in a container (e.g., containers 10 and 410). Thus, controller 21 may regulate a flow of heat transfer fluid to one or more of plates 28 to regulate a temperature of the biopharmaceutical materials held in such a container in slot 25 of cavity 26 of temperature control unit 20. More specifically, controller 21 may cause a heat transfer fluid control portion 22 to circulate heat transfer fluids in plate(s) 28 to raise or lower a temperature of plate(s) 28, thereby lowering or raising the temperature of a container (e.g., containers 10 and 410) which is in contact with plate 28. In this manner, the biopharmaceutical material may have its temperature controlled (i.e., it may be thawed or frozen). Alternatively, such control of heat transfer plates 28 may be performed by controller portion 21 controlling flow of heat transfer fluid to plates 28 in a predetermined manner without feedback from a sensor coupled to plates 28 or the heat transfer fluid. In a further example, a temperature sensor (not shown) could extend through a port or conduit of a container (e.g., container 10) to allow a determination of a temperature of biopharmaceutical materials held therein. A flow of heat transfer fluid or other temperature regulation may be based on such determination.
Also, one or more of plates 28 may be moveable to contact container 10, container 410 and/or any other container when the containers are received in holders (e.g., holders 15 and 415) and the holders are connected to plate 500 and received in slot 25 of cavity 26 of temperature control unit 20, as depicted in
In another embodiment, a temperature control unit includes a heat exchanger having one or more stationary heat transfer surfaces, in which a heat transfer fluid is circulating, for heating, cooling, freezing and or thawing one or more containers and biopharmaceutical materials contained therein. For example, a temperature control unit 820 may include a stationary heat transfer plate 828 for contacting multiple containers (e.g. container 10 and/or 410) on one or on each face of heat transfer plate 828 as depicted in
For example container 10 may be attached to a moveable door 900 of temperature control unit 820. Door 900 may be non-temperature controlled and/or insulated. Also, door 900 may be connected to a central body portion 905 of temperature control unit 820 by connecting rods or arms 907 which are pivotally connected to door 900 and central portion 905 to allow the moveable connection of door 900 between open (e.g., non-contacting position of the container relative to a heat exchange plate 828) and closed (e.g., contacting) positions. The movable door is configured to move to contact the container(s) with one face of heat exchange plate 828 during cooling and/or heating operations. For example, first side 12 of container 10 may contact a heat transfer surface (e.g., heat exchange plate 828) of an interior 826 of temperature control unit 820 through opening 210 to control the temperature of the biopharmaceutical material in container 10. The second (i.e., opposite) side of container 10 may contact the insulated moveable door 900 of the temperature control unit 20 via opening 211.
A latching mechanism 910 maintains the movable doors (e.g., doors 900) closed onto a sealing gasket 930 (
Temperature sensors (not shown) may be mounted at an interface between moveable wall 900 and first side 12 of container 10 through opening 210. The temperature detected at this interface corresponds to the last point to freeze and last point to thaw location of the biopharmaceutical product stored in container 10. One or more of the temperature sensors may detect a temperature of one or more of containers 10 and one or more locations thereon. A controller portion (not shown) of temperature control unit 820 may be coupled to the temperature sensor(s) and to a heat transfer fluid control portion 822 (not shown) of temperature control unit 820. Such heat transfer fluids may be circulated through plate 826 by the heat transfer fluid control portion controlled by the controller portion in response to temperature(s) detected by the temperature sensor(s).
Also, a holder (e.g., holder 15 or 415) may include openings (not shown) configured to receive posts (not shown) of door 900. Holder 15 may thereby be attached to door 900 by receiving one or more posts in one or more openings. Similarly, holder 415 may thereby be attached to door 900 by receiving one or more posts in one or more openings. Although doors 900 are depicted as being connected to central body portion 905 each by four arms 907, the doors could be connected to the central body portion by more or less arms located at various locations along the doors and central body portion. For example, in addition to the exterior placement of the arms on the doors and interior connection thereof to the central body portion depicted, the arms could be connected to both exterior portions of the doors and a central body portion or both to interior portions thereof or a combination of these methods. The selective placement of the arms relative to the doors and the central body portion could allow the pivoting of the doors in various ways away from and back toward the central body portion. Further, the doors could be connected or latched to the central body portion in any number of ways having handles located on an exterior of the temperature control unit or hidden in some way. Moreover, the temperature control unit may be placed on a drip tray to catch any liquids such as biopharmaceutical materials, water, or other liquid coolants which may be produced by the freezing of biopharmaceutical materials, thawing of biopharmaceutical materials, condensation or other incidental leaks.
Also, one or more moveable walls or doors (e.g., doors 900, 1000) may allow compression of a flexible container (e.g., flexible container 10), and hence good thermal contact and substantially constant container depth, when the container is received in a holder (e.g., holder 15) and the holder is received in an interior (e.g., interior 826) of a temperature control unit (e.g., temperature control units 820, 920, 1020, 1100). To compensate for the increased pressure and expansion resulting from the freezing of the biopharmaceutical aqueous solution stored inside the container, a moveable wall or door (e.g., doors 900, 1000) might be spring loaded to allow an increase of distance between a heat exchange plate (e.g., plate 828) and such a movable door (e.g., door 900).
Also, a temperature control unit (e.g., temperature control unit 20, 820, 920, 1100) may be mounted onto a reciprocating or orbital mixer (not shown), thereby allowing the agitation of, and thereby promote thawing and mixing of, biopharmaceutical materials held in a container (e.g., container 10) held therein. Such mixing could be performed for the purpose of thawing and mixing of the biopharmaceutical materials. More particularly, thawing rates of biopharmaceutical materials may be accelerated by generation of movement of partially-thawed solid-liquid mixture comprising a biopharmaceutical solution against walls of a container which may contact heat transfer surfaces, such as plates 28.
In another embodiment depicted in
As depicted in
In another example depicted in
Also, it will be understood by one skilled in the art that various holders (e.g., holder 15 and holder 615) may be integral to various sized containers (e.g., container 10 and container 610) and may be received in a temperature control unit (e.g., temperature control unit 20). Further, it will be understood to one skilled in the art that a supporting plate (e.g., plate 500) may be attached to holders (e.g., holder 15) in any number of ways which allow the holders to be selectively released therefrom. For example, the plates may include any number of pegs, connectors, clips, openings, or other means for attaching to connecting structures of one or more holders, such as peg openings, clips, fasteners, etc. Also, a supporting plate (e.g., supporting plate 500) may include structures (not shown) allowing the heat transfer plate to stand upright (e.g., maintain a vertical orientation) when attached to such holders having biopharmaceutical materials held in containers thereof. Further, the supporting plate could be any structure configured (e.g., shaped, dimensioned and formed of sufficient strength) to support the holder(s) and to be received in a temperature control unit.
Although the containers are described herein as flexible containers, the containers may be made of a semi-rigid material such as polyethylene or the like. An example of such a container could include a container similar to a standard plastic milk jug. Containers made of such similar semi-rigid materials may benefit from additional rigidity supplied by attachment (e.g., fixedly) to a holder, for example. Further, the containers whether formed of a rigid, flexible or semi-rigid material, contain outer surfaces which may contact the interior surfaces (e.g., heat transfer plates) of a temperature control unit (e.g., temperature control unit 20) so that there is direct contact between the cooled (e.g., to a subzero temperature) or heated interior surfaces of the temperature control unit and the outer surfaces of the container containing biopharmaceutical materials. Alternatively, the outer surfaces of the containers for holding the biopharmaceutical materials may be in contact with air flow in an interior (e.g., interior 25) of the temperature control unit or other means of temperature control (e.g., a blast freezer) to cause the cooling and/or heating of the containers having the biopharmaceutical materials therein to cause the temperature of the biopharmaceutical materials to be controlled.
The biopharmaceutical material in the containers described above may thus be cooled or otherwise thermoregulated (e.g., to a subzero temperature) in temperature control unit 20 or a blast freezer, for example. When such operation is completed, the containers may be removed from temperature control unit 20 by removing the containers and the holders, or other support structures which the containers are received in or connected to, for example. The holders or other support structures holding the containers may be stored in a large chiller or freezer with an interior air temperature of about negative 20 degrees Celsius, for example.
A typical process for processing and/or preserving a biopharmaceutical material is described as follows. One or more containers (e.g., containers 10, 410, 610, or 710) is integrally formed or fixedly (e.g., non-separably) connected to a holder (e.g., holders 15, 415, 615 or 715) as depicted in
Further, the above-described containers may be removed from a freezer or other system for storage of the flexible containers and contents thereof at a controlled temperature. These containers having biopharmaceutical material therein may then be received in a temperature control unit for heating, melting, agitating, mixing and/or thawing the biopharmaceutical material contained in the containers. For example, holder 15 supporting container 10 having frozen biopharmaceutical material therein may be placed in temperature control unit 20 where its temperature may be controlled (e.g. thawed) by heat transfer plate(s) 28. In addition, holder 15 or supporting plate 500 on which holders 15 are secured may be submitted to gentle mixing inside temperature control unit 20 to accelerate the thawing kinetics and to minimize any solute concentration gradient in the thawed liquid. Also, when use of the biopharmaceutical materials held in the container (e.g., containers 10, 410, 610 or 710) is desired, and if the conduit is previously at least partially removed and sealed, the remaining portion of the conduit or other portion of the container may be pierced or otherwise opened to allow fluid communication between an interior or an exterior thereof such that biopharmaceutical materials may be removed.
From the above description, it will be understood to one skilled in the art that the containers described herein may be adapted for use in holders, storage units, support structures, transportation devices, temperature control units, heat exchangers, vessels, and/or processors of various shapes or sizes. Further, the holders, containers, support structures, heat exchangers, temperature control units, and/or processors may be adapted to receive containers of various shapes or sizes. These holders or support structures may be configured for long or short term storage of the containers containing biopharmaceutical materials in liquid or frozen state, or may be adapted to transport the flexible containers containing biopharmaceutical materials in liquid or frozen state. For example, the temperature control unit may be insulated to allow the material to remain at a given temperature for a prolonged period of time. Furthermore, these holders, containers, support structures, temperature control units, heat exchangers, and/or processors may be adapted for utilization with materials other than biopharmaceutical materials. Finally, the storage containers, support structures, temperature control units, or holders may be equipped with various transport mechanisms, such as wheels, glides, sliders, dry-ice storage compartments or other devices to facilitate transport and organization thereof.
While the invention has been depicted and described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions and the like can be made without departing from the spirit of the invention and these are therefore considered to be within the scope of the invention as defined in the following claims.
This application is a divisional of U.S. Ser. No. 11/682,558, filed on Mar. 6, 2007, which claims the benefit of U.S. Provisional Patent Application No. 60/779,823, filed on Mar. 6, 2006, the entire disclosures of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60779823 | Mar 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11682558 | Mar 2007 | US |
| Child | 13213638 | US |
