Patent Application
20230330341
The pharmaceutical industry uses various auto-injectors with pre-filled syringes (PFS). Auto-injector (AI) manufacturers develop AIs for a specific solution volume. If the solution volume requirement changes during development of the AI, then a portion of the AI development process needs to be repeated or changed. This makes the use of auto-injectors in early clinical trials problematic due to the length of time needed to develop the AI with a new solution volume. Further, the dose patients need may be based on their weight. Therefore, there is a need for an AI system and method which uses a pre-filled syringe filled at maximum capacity but has the ability to inject various different volumes of solution.
Further, there is a need for an auto-injector system and method which employs pre-filled syringes with various fill volumes where the AI can inject using all of the various filled pre-filled syringes.
Still further, there is a need for an AI system and method which can easily integrate with various pre-filled syringes and syringe volumes using the same or similar parts.
These and other problems experienced in the art have been addressed and obviated by the present embodiments.
The embodiments comprise auto-injectors and their use with pre-filled syringes. The embodiments comprise an auto-injector system for injecting various solution volumes, comprising: an auto-injector housing having an actuating end and an injection end, the housing comprising; a release mechanism co-axially aligned in the housing near the actuating end; a spring co-axially aligned and in contact with the release mechanism; a pre-filled syringe co-axially aligned in the housing at the injection end, comprising a set capacity syringe barrel having a syringe chamber for holding a plunger cap with a plunger cap length and a solution volume for injecting, wherein the plunger cap retains the solution volume within the syringe chamber; and a syringe needle attached to the syringe barrel for injecting the solution volume; an interchangeable plunger rod having a defined interchangeable plunger rod length and being co-axially aligned in the housing between the spring and the plunger cap; and an interchangeable plunger rod extension having a defined interchangeable plunger rod extension length and being co-axially aligned and contacting the interchangeable plunger rod, wherein the lengths of the spring, interchangeable plunger rod, interchangeable plunger rod extension, and plunger cap define a co-axially aligned and continuous auto-injector system for injecting various solution volumes; and an optional auto-injector cap for covering the auto-injector housing at the injection end.
The embodiments also provide methods for injecting various solution volumes using an auto-injector system, comprising: providing an auto-injector system for injecting various solution volumes, comprising an auto-injector housing having an actuating end and an injection end, the housing comprising a release mechanism co-axially aligned in the housing near the actuating end; a spring co-axially aligned and in contact with the release mechanism; a pre-filled syringe co-axially aligned in the housing at the injection end, comprising a set capacity syringe barrel having a syringe chamber for holding a plunger cap with a plunger cap length and a solution volume, wherein the plunger cap retains the solution volume within the syringe chamber; and a syringe needle attached to the syringe barrel for injecting the solution volume; an interchangeable plunger rod having a defined interchangeable plunger rod length and being co-axially aligned in the housing between the spring and the plunger cap; and an interchangeable plunger rod extension having a defined interchangeable plunger rod extension length and being co-axially aligned and contacting the interchangeable plunger rod, wherein the lengths of the spring, interchangeable plunger rod, interchangeable plunger rod extension, and plunger cap define a co-axially aligned and continuous auto-injector system for injecting various solution volumes; and an optional auto-injector cap for covering the auto-injector housing at the injection end; and injecting the various solution volumes.
The skilled artisan will understand that the drawings, described below, are for illustration purposes only. The drawings are not intended to limit the scope of the present teachings or claims in any way.
This disclosure describes embodiments related to pre-filled syringes and methods of using them.
For the purpose of interpreting this specification, the following definitions will apply. In the event that any definition set forth below conflicts with the usage of that word in any other document, including any document incorporated herein by reference, the definition set forth below shall always control for purposes of interpreting this specification and its associated claims unless a contrary meaning is clearly intended (for example in the document where the term is originally used).
Whenever appropriate, terms used in the singular will also include the plural and vice versa. The use of “a” herein means “one or more” unless stated otherwise or where the use of “one or more” is clearly inappropriate.
The use of “or” means “and/or” unless stated otherwise. The use of “comprise,” “comprises,” “comprising,” “include,” “includes,” and “including” are interchangeable and are not limiting. The terms “such as,” “for example,” and “e.g.” also are not intended to be limiting. For example, the term “including” shall mean “including, but not limited to.”
As used herein, the term “about” refers to +/- 10% of the unit value provided.
As used herein, the term “substantially” refers to the qualitative condition of exhibiting a total or approximate degree of a characteristic or property of interest. One of ordinary skill in the biological arts will understand that biological and chemical phenomena rarely, if ever, achieve or avoid an absolute result because of the many variables that affect testing, production, and storage of biological and chemical compositions and materials, and because of the inherent error in the instruments and equipment used in the testing, production, and storage of biological and chemical compositions and materials. The term “substantially” is, therefore, used herein to capture the potential lack of completeness inherent in many biological and chemical phenomena.
Referring now to the figures,
The optional auto-injector cap 230 contacts or can be removably attached to the auto-injector housing 110. In most embodiments the optional auto-injector cap 230 will be designed for ease of removal. Various options for joining the optional auto-injector cap 230 to the syringe cap 220 and/or auto-injector housing 110 include and are not limited to the use of a set of threads for mating the ends, attachment via clips or fasteners or any other types of devices or means known in the art. The optional auto-injector cap 230 can be designed of plastic, metal, composite or similar material know or used in the art. The optional auto-injector cap 230 is positioned and disposed at the injection end of the auto-injector system 100.
The auto-injector system 100 is designed for housing the release mechanism 130 and spring 140 which is used for compressing and injecting a solution volume 250 which is placed in the auto-injector system 100 (typically inside the pre-filled syringe 170 and the syringe chamber 190). The release mechanism 130 is not shown in detail in the drawings for ease of viewing since there are many possible designs and orientations for the actuating parts and components. The release mechanism 130 is simply used for actuating the device and injection when the device is actuated by a user to make an injection. Various springs, components, and mating parts may be employed cooperatively and efficiently to accomplish this purpose. Various different parts and release mechanisms 130 are known and used in the art.
The spring 140 can comprise plastic, metal, an alloy, or other similar type material known or used in the art. Various shapes, sizes, and quantities may be employed with the present embodiments. The spring 140 is particularly designed to keep the internal parts under compression so that when the release mechanism 130 is actuated the motion or force is translated to the other components to actuate the injection and inject the solution volume. In other words, the parts define a continuous auto-injector system for injecting various solution volumes.
The interchangeable plunger rod 150 can comprise various shapes, designs, and materials known or used in the art including but not limited to plastic, resin, metal, and composite materials. The interchangeable plunger rod 150 can be hollow or solid. The interchangeable plunger rod 150 lengths can vary or be fixed depending upon the pre-filled syringe and embodiment. Preferable length of the interchangeable plunger rod 150 is from about 5 to 80 millimeters. Other sizes, shapes, and lengths are within the anticipated scope of the present embodiments. The interchangeable plunger rod 150 can be retained or replaced in certain other injections for different patients. For instance, in certain embodiments the interchangeable plunger rod 150 can be replaced with a second interchangeable plunger rod 150′ having a second interchangeable plunger rod length. In other embodiments, the interchangeable plunger rod 150 can be maintained using the same interchangeable plunger rod 150 and providing the defined interchangeable plunger rod length.
The interchangeable plunger rod extension 160 can comprise various shapes, designs, and materials know or used in the art including, but not limited to plastic, resin, metal, and composite materials. The interchangeable plunger rod extension 160 can be solid or hollow. The interchangeable plunger rod extension 160 lengths can vary or be fixed depending upon the pre-filled syringe and embodiment. Preferable lengths of the interchangeable plunger rod extension 160 are from about 5 to 80 millimeters. Other sizes, shapes, and lengths are within the anticipated scope of the present embodiments. The interchangeable plunger rod extension 160 can be replaced or changed in a different injection run depending upon the embodiment. For instance, in a different injection run the interchangeable plunger rod extension 160 can be replaced with a second interchangeable plunger rod extension 160′ having a second interchangeable plunger rod extension length. In other embodiments, the interchangeable plunger rod extension 160 can be maintained with the defined interchangeable plunger rod extension length.
The plunger cap 165 is typically associated with the pre-filled syringe. It is described separately here since it represents an important component related to the embodiments of the invention. It can comprise a portion of the interchangeable plunger rod extension 160, interchangeable plunger rod 150, or serve as a separate stand-alone component in contact with one or more of these components. The plunger cap 165 can comprise rubber or any similar type of material known or used in the art. A portion or side of the plunger cap 165 is typically designed to contact a solution for injection such as solution volume 250. A force can be supplied to the plunger cap 165 via interchangeable plunger rod 150, interchangeable plunger rod extension 160 or any other parts known or provided in an embodiment. The force is used to slide plunger cap 165 to compress and inject or inject the solution volume 250 from the pre-filled syringe 170. The plunger cap 165 can be varied or a fixed length and width. Preferably the length of plunger cap 165 is fixed and can be in a length of about 5 to 6 millimeters. Other sizes and shapes known and used in the art can be employed with the present embodiments. The plunger cap 165 is positioned within the syringe chamber 190 by the filling company based on the solution volume 250. The plunger cap 165 is placed adjacent to the solution volume 250 within the syringe chamber 190. The plunger cap 165 can be used or employed in a number of injection runs. In additional injection runs the plunger cap 165 is typically retained and not replaced or changed. However, it could be imagined in certain embodiments that a new or different plunger cap 165 or 165′ could be employed.
The pre-filled syringe 170 comprises a syringe barrel 180, a syringe chamber 190, a solution volume 250, a plunger cap 165, a syringe needle 210, and a syringe cap 220. The pre-filled syringe 170 is designed to fit within the auto-injector housing 110. Various pre-filled syringes 170 known in the art can be used with the present auto-injector system 100. The types and sizes of the pre-filled syringes 170 include and are not limited to the following: 0.5 mL, 1.0 mL, 1.5 mL, and 2.0 mL. The pre-filled syringe 170 can comprise plastic or other similar type material used or known in the art. Other shapes, sizes, and designs are possible which are known and used in the art and which can be employed with the present embodiments. The use of a pre-filled syringe 170 provides for an unexpected benefit of not requiring complete part replacement or delay for set up of auto-injector system 100. In certain other embodiments it could be further envisioned that the pre-filled syringe 170 could also be replaced or changed if necessary or desirable.
The syringe barrel 180 and the syringe chamber 190 can vary in shape, size, and volume. Preferable volumes include and are not limited to 0.5 mL, 1.0 mL, 2.0 mL. Other volumes not described which are larger, smaller, or within the above described range are within the scope of the present embodiments. The syringe barrel 180 can comprise plastic, metal, composite material or any other known or unknow material which is used in the art.
The syringe needle 210 is used for injecting the solution volume 250. The syringe needle 210 serves both to puncture a user’s skin and to deliver the solution volume 250 through subcutaneous delivery. It can be anticipated that the syringe needle 210 could also be employed to deliver the solution volume 250 in other ways or designs known or not known in the art. The syringe needle 210 can comprise metal, composite, alloy or other similar types of materials known or used in the art.
The syringe cap 220 is used to cover the end of the syringe needle 210. The syringe cap 220 along with the auto-injector cap 230 prevent needle sticks when the auto-injector system 100 is not in use. The syringe cap 220 can comprise plastic, metal, or other composite material known or used in the art. Various shapes and designs of the syringe cap 220 can also be anticipated with the present embodiments.
The syringe chamber 190 is a fixed volume. However, the solution volume 250 can vary in amount and composition within the syringe chamber 190. The position of the plunger cap 165 is set in a pre-filled syringe determined by the solution volume 250. The position of the plunger cap 165 is typically set adjacent to the solution volume 250 by the user or filling manufacturer. An auto-injector is designed to inject a set solution volume 250 based on the position of the plunger cap 165 within the syringe chamber 190. If the solution volume 250 is changed by the filling manufacturer within the pre-filled syringe chamber 190 and, therefore, the plunger cap 165 position is changed, the appropriate size interchangeable plunger rod extension 160 can be used in combination with the interchangeable plunger rod 150 to fill the void left by the changed plunger cap 165 position. This provides for increased flexibility in auto-injector systems that was not possible in the past.
The solution volume 250 can comprise any solution, drug, or biologic which would be known or delivered in the pre-filled syringe or biological arts for subcutaneous injection. For instance, various drugs, biologics, and solutions can be delivered using the embodiments of the invention. Other anticipated drugs or therapeutics used for delivery could include those molecules used or developed in the fields of Oncology, gene therapy and cell therapy. Solution volume 250 can also be changed or adjusted during additional or multiple injection runs. For instance, it can be imagined in a different injection run if one or more of the components are changed or adjusted, the solution volume 250 could be changed or adjusted to inject a second solution volume 250′.
Table 1 shows the various configurations of components of the first embodiment of the invention using a 1.0 mL capacity pre-filled syringe 170. In the first embodiment the interchangeable plunger rod 150 length is maintained at a constant 50 mm, the interchangeable plunger rod extension 160 is changed in length, and the syringe chamber 190 is kept constant at 1.0 mL but is filled with various fill volumes as shown in the table. This arrangement and orientation allow a manufacturer to quickly and effectively adjust certain components to inject various solution volumes 250 or 250′.
As shown in Table 1 it can be observed in a 1.0 mL capacity syringe that various solution volumes (based on fill volume) of 1.0, 0.75, 0.5, and 0.25 mL can be injected from an AI comprising that same 1.0 mL capacity pre-filled syringe 170 while replacing the interchangeable plunger rod extension 160 with lengths of 0, 8, 16, and 24 millimeters, while the interchangeable plunger rod 150 length is fixed at 50 millimeters. The ability to inject various amounts of solution volume 250 or 250′ makes it a very flexible and efficient system without the need for redesigning and redeveloping another version of the AI when a different solution volume 250 or 250′ is required.
Table 2 shows similar data and results but using a larger 2.0 mL pre-filled syringe 170 and method.
Table 2 shows a 2.0 mL capacity pre-filled syringe 170 with various solution volumes 250 (Fill/Solution Volume) of 2.0, 1.5, 1.0, and 0.5 mL Again the interchangeable plunger rod 150 length and syringe chamber 190 volumes are fixed at 50 mL and 2.0 mL respectively. The interchangeable plunger rod extension 160 lengths are 0, 10, 20, and 30 mm respectively.
As shown in Table 3 it can be observed in a 1.0 mL capacity syringe that various solution volumes of 1.0, 0.75, 0.5, and 0.25 mL can be injected from the a 1.0 mL capacity syringe while using varying interchangeable plunger rod 150 lengths of 40, 48, 56, 64 mm, while the interchangeable plunger rod extension 160 length is fixed at 10 mm. The ability to inject various amounts of solution volume 250 makes it a very flexible and efficient system without the need for frequent system changes or adjustments when a different solution volume 250 or 250′ is desired.
Table 4 shows a 2.25 mL capacity syringe with various solution volumes of 2.0, 1.5, 1.0, and 0.5 mL. The interchangeable plunger rod extension 160 length and syringe chamber 190 volumes are fixed at 10 mm and 2.0 mL respectively. The interchangeable plunger rod 150 lengths are 40, 50, 60 and 70 mm respectively.
Table 5 shows the various configurations of the components of the third embodiment of the invention using a 1.0 mL capacity pre-filled syringe 170. In the first embodiment the interchangeable plunger rod 150 length is maintained at a constant 50 mm length, the interchangeable plunger rod extension 160 is changed in length, and the syringe chamber 190 is kept constant at 1.0 mL. This arrangement and orientation allow a manufacturer to quickly and effectively adjust certain components to inject various solution volumes 250 or 250′. As shown in Table 5 it can be observed in a 1.0 mL capacity syringe that various solution volumes 250 of 1.0, 0.75, 0.5, and 0.25 mL can be injected from a 1.0 mL capacity syringe while varying the combined lengths of the interchangeable plunger rod extension 160 and the interchangeable plunger rod 150 at 50, 58, 66, and 74 mm when telescopically sliding the plunger extension 160 along the interchangeable plunger rod 150 and locking at the discrete lengths when the tabs are engaged with the appropriate set of slots. The ability to inject various amounts of solution volume 250 or 250′ makes it a very flexible and efficient system without the need for redesigning and redeveloping another version of the AI when a different solution volume 250 or 250′ is required.
Table 6 shows similar data and results but using a larger 2.0 mL pre-filled syringe 170 and method. Table 6 shows a 2.0 mL capacity syringe with various solution volumes 250 of 2.0, 1.5, 1.0, and 0.5 mL. The chamber 190 volume is fixed at 2.0 mL, while varying the combined adjustable lengths of the interchangeable plunger rod extension 160 and the interchangeable plunger rod 150 at 50, 60, 70, and 80 mm in the same way as previously described for the 1.0 mL capacity.
Having discussed the embodiments of the invention, a description of their assembly is now in order.
The release mechanism 130 is coaxially aligned and positioned in the auto-injector housing 110 near the actuating end of the housing 110. It slides all the way into the auto-injector housing 110 until it abuts the actuating end of the device. The spring 140 is then co-axially aligned and inserted to abut the release mechanism 130. Depending upon the embodiment either the interchangeable plunger rod 150 or the interchangeable plunger rod extension 160 is co-axially aligned and inserted into the auto-injector housing 110. In the first embodiment the interchangeable plunger rod 150 is co-axially aligned and contacts the spring 140 and interchangeable plunger rod extension 160.
Next, the pre-filled syringe 170 is inserted co-axially into the injection end of the auto-injector housing 110 until the plunger cap 165 abuts the end of the interchangeable plunger rod extension 160 or the interchangeable plunger rod 150. Once all the components have been assembled together and inserted into the auto-injector system 100, the cap 230 can be attached to enclose the auto-injector housing 110 and internal components. This process can be repeated, or parts changed, replaced or adjusted in different injection runs and/or embodiments.
Referring to
As previously discussed in
Referring to
In summary, the embodiments provide an auto-injector system 100 for injecting various solution volumes 250, comprising: an auto-injector housing 110 having an actuating end and an injection end, the housing comprising; a release mechanism 130 co-axially aligned in the housing near the actuating end; a spring 140 co-axially aligned and in contact with the release mechanism 130; a pre-filled syringe 170 co-axially aligned in the housing 110 at the injection end, comprising a set capacity syringe barrel 180 having a syringe chamber 190 for holding a plunger cap 165 with a plunger cap length and a solution volume 250 for injecting, wherein the plunger cap 165 retains the solution volume 250 within the syringe chamber 190; and a syringe needle 210 attached to the syringe barrel 180 for injecting the solution volume 250; an interchangeable plunger rod 150 having a defined interchangeable plunger rod length and being co-axially aligned in the housing 110 between the spring 140 and the plunger cap 165; and an interchangeable plunger rod extension 160 having a defined interchangeable plunger rod extension length and being co-axially aligned and contacting the interchangeable plunger rod 150, wherein the lengths of the spring 140, interchangeable plunger rod 150, interchangeable plunger rod extension 160, and plunger cap 165 define a co-axially aligned and continuous auto-injector system 100 for injecting various solution volumes 250; and an optional auto-injector cap 230 for covering the auto-injector housing 110 at the injection end.
Further, the embodiments provide an auto-injector system 100 wherein the interchangeable plunger rod 150 is co-axially aligned and contacts the spring 140 and interchangeable plunger rod extension 160.
Further, the embodiments provide an auto-injector system 100, wherein the pre-filled syringe 170 set capacity of the syringe barrel 180 and syringe chamber 190 is in a range of from 1.0 to 2.0 mL, the interchangeable plunger rod 150 length is in a range of from 5 to 80 mm, the interchangeable plunger rod extension 160 length is in a range of from 5 to 80 mm, the plunger cap 165 length is in a range of from 5 to 6 mm, and a solution volume 250 is in the range of from 0.1 to 1.9 mL.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod 150 is replaced with a second interchangeable plunger rod 150′, the second interchangeable plunger rod 150′ having a length in the range of from 5 to 80 mm, the interchangeable plunger rod extension 160 is replaced with a second interchangeable plunger rod extension 160′, the second interchangeable plunger rod extension 160′ having a length in a range of from 5 to 80 mm, the plunger cap 165 length is in a range of from 5 to 6 mm, and the second solution volume 250′ is in the range of 0.1 to 1.9 ml.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod 150 length is 50 mm, the interchangeable plunger rod extension 160 length is 0 mm, the plunger cap 165 length is 5 mm, the solution volume 250 is 1.0 mL, the second interchangeable plunger rod 150′ length is 50 mm, the second interchangeable plunger rod extension 160′ length is 24 mm, the plunger cap 165 length is 5 mm, and the second solution volume 250′ is 0.25 mL.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod extension 160 is co-axially aligned and contacts the spring 140 and the interchangeable plunger rod 150.
Further, the embodiments provide an auto-injector system 100 wherein the pre-filled syringe 170 set capacity of the syringe barrel 180 and syringe chamber 190 is in a range of from 1.0 to 2.0 mL, the interchangeable plunger rod 150 length is in a range of from 5 to 80 mm, the interchangeable plunger rod extension 160 length is in a range of from 5 to 80 mm, the plunger cap 165 length is in a range of from 5 to 6 mm, and a solution volume 250 is in the range of from 0.1 to 1.9 mL.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod 150 is replaced with a second interchangeable plunger rod 150′, the second interchangeable plunger rod 150′ having a length in the range of from 5 to 80 mm, the interchangeable plunger rod extension 160 is replaced with a second interchangeable plunger rod extension 160′, the second interchangeable plunger rod extension 160′ length is in a range of from 5 to 80 mm, the plunger cap 165 length is in a range of from 5 to 6 mm, and the second solution volume 250 is in the range of 0.1 to 1.9 ml.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod 150 length is 40 mm, the interchangeable plunger rod extension 160 length is 10 mm, the plunger cap 165 length is 5 mm, the solution volume 250 of 1.0 mL is injected, the second interchangeable plunger rod 150′ length is 64 mm, the second interchangeable plunger rod extension 160′ length is 10 mm, the plunger cap 165 length is 5 mm, and the second solution volume 250′ is 0.25 mL.
Further, the embodiments provide an auto-injector system 100, wherein the interchangeable plunger rod 150 is coaxially aligned and fits telescopically within the interchangeable plunger rod extension 160, wherein the interchangeable plunger rod 150 and interchangeable plunger rod extension 160 define an adjustable interchangeable plunger rod assembly which contacts the spring 140 and the plunger cap 165, the adjustable interchangeable plunger rod assembly having a length in a range of from 5 to 80 mm, and a solution volume 250 in the range of 0.25 to 1.0 mL.
Further, the embodiments provide an auto-injector system 100, wherein the adjustable interchangeable plunger rod assembly is adjusted to a second adjustable interchangeable plunger rod assembly length and a second solution volume 250′ is injected, wherein the second adjustable interchangeable plunger rod length is in a range of from 5 to 80 mm, and the second solution volume injected is in the range of 0.25 to 1.0 mL.
Further, the embodiments provide an auto-injector system 100, wherein the adjustable interchangeable plunger rod assembly length is 50 mm, the plunger cap 165 length is 5 mm, a solution volume 250 of 1.0 mL is injected, the second adjustable interchangeable plunger rod assembly length is 74 mm, the plunger cap length 165 is 5 mm, and the second solution volume 250′ injected is 0.25 mL.
Having now described each of the embodiments and their assembly, a description of the method of using the device is now in order.
The syringe needle 210 is then exposed and ready for use for an injection. The auto-injector 100 is then aligned with the skin surface of the user as shown in
The embodiments further provide methods for injecting various solution volumes using an auto-injector system 100, comprising: providing an auto-injector system 100 for injecting various solution volumes 250, comprising an auto-injector housing 110 having an actuating end and an injection end, the housing 119 comprising a release mechanism 130 co-axially aligned in the housing near the actuating end; a spring 140 co-axially aligned and in contact with the release mechanism 130; a pre-filled syringe 170 co-axially aligned in the housing 110 at the injection end, comprising a set capacity syringe barrel 180 having a syringe chamber 190 for holding a plunger cap 165 with a plunger cap length and a solution volume 250, wherein the plunger cap 165 retains the solution volume 250 within the syringe chamber 190; and a syringe needle 210 attached to the syringe barrel 190 for injecting the solution volume 250; an interchangeable plunger rod 150 that’s interchangeable having a defined interchangeable plunger rod 150 length and being co-axially aligned in the housing 110 between the spring 140 and the plunger cap 165; and an interchangeable plunger rod extension 160 that’s interchangeable having a defined interchangeable plunger rod extension 160 length and being co-axially aligned and contacting the interchangeable plunger rod 150, wherein the lengths of the spring 140, interchangeable plunger rod 150, interchangeable plunger rod extension 160, and plunger cap 165 define a co-axially aligned and continuous auto-injector system 100 for injecting various solution volumes 250 or 250′; and an optional auto-injector cap 230 for covering the auto-injector housing 110 at the injection end; and injecting the various solution volumes 250 or 250′.
Further provided are methods comprising replacing the interchangeable plunger rod extension 160 with a second interchangeable plunger rod extension 160′ having a second interchangeable plunger rod extension 160′ length and injecting a second solution volume 250′.
Further provided are methods comprising replacing the interchangeable plunger rod 150 with a second interchangeable plunger rod 150′ having a second interchangeable plunger rod 150′ length and injecting a second solution volume 250′.
Further provided are methods wherein only a portion of the solution volume 250 or 250′ in the syringe chamber 190 is injected.
Further provided are methods where only a portion of the solution volume 250 or 250′ from the syringe chamber 190 is injected when the plunger cap 165 is initially positioned at the end of the syringe chamber 190 closer to the actuating end of the auto-injector housing 110 and then only partially compressed in the syringe chamber 190 toward the injection end.
This application claims the benefit of U.S. Provisional Pat. Application No. 63/088,515, filed on Oct. 7, 2020, the disclosure of which is hereby incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2021/050355 | 9/15/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63088515 | Oct 2020 | US |
