FIELD OF THE INVENTION
The present disclosure relates to auto-injectors and more particularly, relates to an auto-
5 injector assembly having a plunger and adapted to operate to deliver different volumes of a
drug into an injection site.
BACKGROUND
Auto-injectors are widely used for direct delivery of drugs into a patient's body.
Nowadays, there are a plethora of auto-injectors available in the market. The existing auto-
10 injectors are mainly capable of delivering a predetermined dose of medication to the patient.
Typically, the conventional auto-injector is adapted to deliver a predetermined dosage of a
drug to a patient.
As is generally known, each drug requires to be delivered in different volumes to a
patient. The volume may also change depending on the patient, for example, based on a
15 condition and the age of the patient. Similarly, there are multiple other factors contributing in
determining a dosage of a drug to be injected into the patient's body. Therefore, same drug
may have to be delivered in different volumes to different patients for effective treatment.
However, a manufacturer is required to manufacture a specific auto-injector for a predefined
volume of drug to be administered.
20 Therefore, delivering a specific volume of a drug would require construction of a
particular auto-injector that is capable of delivering the predetermined dosage to the patient.
Owing to such constructional limitation, for dosage of different volumes, multiple autoinjectors
are required. Therefore, for a consumer, it is inconvenient to purchase, operate, and
maintain multiple auto-injectors. On the other hand, a drug manufacturer also has to
25 manufacture multiple auto-injectors for different drugs that require different dosage settings.
For example, in terms of infrastructure of the manufacturing plant, the manufacturer may have
to make significant effort and investment.
There are a few device manufacturers offering changes to constituent components of
the auto-injectors allowing for setting variable dose of drugs for delivery. However, the
30 manufacturing of such auto-injectors demands significant assembly-line changes in the
manufacturing plant. Consequently, an overall operational cost of the auto-injectors is also
high.
1
3
SUMMARY
This summary is provided to introduce a selection of concepts, in a simplified format,
that are further described in the detailed description of the invention. This summary is neither
intended to identify key or essential inventive concepts of the invention and nor is it intended
5 for determining the scope of the invention.
In an embodiment of the present disclosure, an auto-injector assembly is disclosed. The
auto-injector assembly includes a housing having a proximal end and a distal end, a syringe
assembly disposed adjacent to the proximal end of the housing and adapted to store a
predetermined volume of a drug to be administered through a needle, a needle guard disposed
10 to surround the syringe assembly such that a portion of the needle guard is adapted to extend
out of the housing in an initial state and to retract into the housing when the portion is pressed
on to an injection site, a spring holder disposed adjacent to the distal end of the housing and
adapted to hold a dose delivery spring in a compressed state, a locking unit disposed inside
the spring holder and adapted to keep the spring holder in a locked state with the housing, and
15 a plunger engaged with the spring holder and adapted to move towards the syringe assembly
when the spring holder is unlocked. A position of engagement of the plunger with the spring
holder is adapted to change for controlling a travelling distance of the plunger within the
housing based on the predetermined volume of the drug in the syringe assembly. The needle
guard, when being retracted, is adapted to push the locking unit further into the spring holder,
20 unlocking the spring holder from the housing such that the plunger is moved towards the
syringe assembly for administering the drug into the injection site.
To further clarify the advantages and features of the present invention, a more particular
description of the invention will be rendered by reference to specific embodiments thereof,
which is illustrated in the appended drawings. It is appreciated that these drawings depict only
25 typical embodiments of the invention and are therefore not to be considered limiting of its
scope. The invention will be described and explained with additional specificity and detail
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present invention will become
30 better understood when the following detailed description is read with reference to the
accompanying drawings in which like characters represent like parts throughout the drawings,
wherein:
Figure 1 illustrates a perspective view of an auto-injector assembly, according to an
embodiment of the present disclosure;
2
4
Figure 2 illustrates an exploded view of the auto-injector assembly depicting various
constituent components, according to an embodiment of the present disclosure;
Figure 3 illustrates another exploded view of the auto-injector assembly, according to
an embodiment of the present disclosure;
5 Figure 4 illustrates a sectional view of the auto-injector assembly depicting various
constituent components, according to an embodiment of the present disclosure;
Figure 5 illustrates a sectional view of a portion of the auto-injector assembly depicting
locking of a spring holder with a housing, according to an embodiment of the present
disclosure;
10 Figure 6 illustrates a sectional view of the auto-injector assembly depicting unlocking
of the spring holder owing to movement of a needle guard, according to an embodiment of
the present disclosure;
Figure 7 A illustrates a sectional view of the auto-injector assembly depicting position
of constituent components in an initial state, according to an embodiment of the present
15 disclosure;
Figure 7B illustrates a sectional view of the auto-injector assembly depicting position
of constituent components after drug is administered, according to an embodiment of the
present disclosure;
Figure 8A illustrates positioning of the needle guard with respect to a syringe holder in
20 the initial state, according to an embodiment of the present disclosure;
Figure 8B illustrates positioning of the needle guard with respect to the syringe holder
after the drug is administered, according to an embodiment of the present disclosure; and
Figure 9 illustrates an example depicting usage of the auto-injector assembly by a user,
according to an embodiment of the present disclosure.
25 Further, skilled artisans will appreciate that elements in the drawings are illustrated for
simplicity and may not have been necessarily been drawn to scale. For example, the flow
charts illustrate the method in terms of the most prominent steps involved to help to improve
understanding of aspects of the present invention. Furthermore, in terms of the construction
of the device, one or more components of the device may have been represented in the
30 drawings by conventional symbols, and the drawings may show only those specific details
that are pertinent to understanding the embodiments of the present invention so as not to
obscure the drawings with details that will be readily apparent to those of ordinary skill in the
art having benefit of the description herein.
3
5
DETAILED DESCRIPTION OF FIGURES
For the purpose of promoting an understanding of the principles of the invention,
reference will now be made to the embodiment illustrated in the drawings and specific
language will be used to describe the same. It will nevertheless be understood that no
5 limitation of the scope of the invention is thereby intended, such alterations and further
modifications in the illustrated system, and such further applications of the principles of the
invention as illustrated therein being contemplated as would normally occur to one skilled in
the art to which the invention relates. Unless otherwise defined, all technical and scientific
terms used herein have the same meaning as commonly understood by one of ordinary skilled
10 in the art to which this invention belongs. The system, methods, and examples provided herein
are illustrative only and not intended to be limiting.
For example, the term "some" as used herein may be understood as "none" or "one"
or "more than one" or "all." Therefore, the terms "none," "one," "more than one," "more than
one, but not all" or "all" would fall under the definition of "some." It should be appreciated
15 by a person skilled in the art that the terminology and structure employed herein is for
describing, teaching and illuminating some embodiments and their specific features and
elements and therefore, should not be construed to limit, restrict or reduce the spirit and scope
of the present disclosure in any way.
For example, any terms used herein such as, "includes," "comprises," "has,"
20 "consists," and similar grammatical variants do not specify an exact limitation or restriction,
and certainly do not exclude the possible addition of one or more features or elements, unless
otherwise stated. Further, such terms must not be taken to exclude the possible removal of
one or more of the listed features and elements, unless otherwise stated, for example, by using
the limiting language including, but not limited to, "must comprise" or "needs to include."
25 Whether or not a certain feature or element was limited to being used only once, it
may still be referred to as "one or more features" or "one or more elements" or "at least one
feature" or "at least one element." Furthermore, the use of the terms "one or more" or "at least
one" feature or element do not preclude there being none of that feature or element, unless
otherwise specified by limiting language including, but not limited to, "there needs to be one
30 or more ... " or "one or more element is required."
Unless otherwise defined, all terms and especially any technical and/or scientific
terms, used herein may be taken to have the same meaning as commonly understood by a
person ordinarily skilled in the art.
4
6
Reference is made herein to some "embodiments." It should be understood that an
embodiment is an example of a possible implementation of any features and/or elements of
the present disclosure. Some embodiments have been described for the purpose of explaining
one or more of the potential ways in which the specific features and/or elements of the
5 proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.
Use of the phrases and/or terms including, but not limited to, "a first embodiment," "a
further embodiment," "an alternate embodiment," "one embodiment," "an embodiment,"
"multiple embodiments," "some embodiments," "other embodiments," "further
embodiment", "furthermore embodiment", "additional embodiment" or other variants thereof
10 do not necessarily refer to the same embodiments. Unless otherwise specified, one or more
particular features and/or elements described in connection with one or more embodiments
may be found in one embodiment, or may be found in more than one embodiment, or may be
found in all embodiments, or may be found in no embodiments. Although one or more features
and/or elements may be described herein in the context of only a single embodiment, or in the
15 context of more than one embodiment, or in the context of all embodiments, the features
and/or elements may instead be provided separately or in any appropriate combination or not
at all. Conversely, any features and/or elements described in the context of separate
embodiments may alternatively be realized as existing together in the context of a single
embodiment.
20 Any particular and all details set forth herein are used in the context of some
embodiments and therefore should not necessarily be taken as limiting factors to the proposed
disclosure.
The present disclosure relates to an auto-injector assembly having a plunger and capable
of administering different volumes of a drug. The position of the plunger can be adjusted to
25 vary the travelling distance within a housing, based on different volumes of a drug to be
delivered to a patient. The position has to be adjusted such that the plunger can travel the
required distance to push the drug out of a syringe assembly. The plunger is adapted to be
engaged at different positions with a spring holder based on dosage requirement for varying
the travelling distance of the plunger within the housing. This adjustment of the position of
30 the plunger happens during the manufacturing stage only, for example, by the manufacturer,
depending on a predefined volume of the drug to be administered by a particular device.
Therefore, the user is not required to make any adjustment to the device and can directly use
the device.
5
7
The auto-injector assembly may also include one or more stoppers on an inner surface
of the housing for engaging the spring holder, restricting the movement of the plunger for
administering the drug, unless the user manually activates the device. Only when the spring
holder is disengaged from the stoppers, which happens upon manual activation by the user,
5 the plunger is adapted to move to push the drug into the injection site.
For the sake of clarity, the first digit of a reference numeral of each component of the
present disclosure is indicative of the Figure number, in which the corresponding component
is shown. For example, reference numerals starting with digit "1" are shown at least in Figure
1. Similarly, reference numerals starting with digit "2" are shown at least in Figure 2.
10 Embodiments of the present invention will be described below in detail with reference
to the accompanying drawings.
Figure 1 illustrates a perspective view of an auto-injector assembly 100, according to
an embodiment of the present disclosure. Figure 2 illustrates an exploded view of the autoinjector
assembly 100 depicting various constituent components, according to an embodiment
15 of the present disclosure. Figure 3 illustrates another exploded view of the auto-injector
assembly 100, according to an embodiment of the present disclosure. Figure 4 illustrates a
sectional view of the auto-injector assembly 100 depicting various constituent components,
according to an embodiment of the present disclosure. Referring to Figure 1, Figure 2, Figure
3, and Figure 4, the auto-injector assembly 100 may include, but is not limited to, a housing
20 102, a syringe assembly 202 having a needle 406, a needle shield 408, a cap 208, a syringe
holder 210, a needle guard 212, a needle guard spring 214, a dose delivery spring 216, a spring
holder 218, a locking unit 220, a plunger 222.
In an embodiment, the housing 102 may include a proximal portion 108 and a distal
portion 110. The proximal portion 108 may accommodate the positioning of the syringe
25 assembly 202, the needle shield 408, the cap 208, the syringe holder 210, the needle guard
212, and the needle guard spring 214. Further, the distal portion 110 may accommodate the
dose delivery spring 216, the spring holder 218, the locking unit 220, and the plunger 222.
The housing 102 may include a proximal end 104 and a distal end 106. The syringe
assembly 202 may be disposed adjacent to the proximal end 104. The syringe assembly 202
30 may be supported within the housing 102 through the syringe holder 210. The syringe
assembly 202 may be adapted to store a predetermined volume of a drug to be administered.
The syringe assembly 202 may include the needle 406 through which the drug is administered
into the injection site.
6
8
In an embodiment, the needle shield 408 may be adapted to encapsulate the needle 406.
Further, the needle shield 408 may be fixed with the cap 208, which may be adapted to close
the proximal end 104 of the housing 102 when not in use. The cap 208 and the needle shield
408 may be adapted to be removed before initiating the process of administering of the drug.
5 Further, the needle guard 212 may be disposed to surround the syringe assembly 202.
The needle guard 212 may be positioned such that a portion of the needle guard 212 is adapted
to extend out of the housing 102 in an initial state. The auto-injector assembly 100 is activated
by the user, for example, by pressing the proximal end 104 on the injection site. When the
extended portion is pressed on to an injection site, the needle guard 212 may be adapted to
10 retract into the housing 102. In this process, the needle 406 of the syringe assembly 202 is
extended for being inserted into the injection site and to return to an original position when
the drug is administered.
In an embodiment, the needle guard spring 214 may be adapted to support the movement
of the needle guard 212 within the housing 102 for administering the drug. The needle guard
15 spring 214 may be adapted to be disposed between an inner surface of the housing 102 and
an outer surface of the needle guard 212. Therefore, the space between the housing 102 and
the needle guard 212 accommodates the movement, i.e., compression and expansion, of the
needle guard spring 214. The needle guard spring 214 may accommodate the extension and
retraction of the needle guard 212 within the housing 102 during the administering of the drug.
20 The auto-injector assembly 100 may further include the spring holder 218 disposed
adjacent to the distal end 106 of the housing 102. The spring holder 218 may be adapted to
hold the dose delivery spring 216 in a compressed state. The dose delivery spring 216 may be
disposed between the inner surface of the housing 102 and an outer surface of the spring
holder 218. Such positioning of the dose delivery spring 216 outside the plunger 222 allows
25 accommodating drugs having higher viscosity, for example, by changing spring stiffness, say,
by increasing wire diameters or an overall spring diameter. In another embodiment, the dose
delivery spring 216 may be disposed inside the spring holder 218.
The spring holder 218 may be adapted to be in a locked state with the housing 102. In
an embodiment, the locking unit 220 may be disposed inside the spring holder 218 and
30 adapted to keep the spring holder 218 in the locked state with the housing 102.
Figure 5 illustrates a sectional view of a portion of the auto-injector assembly 100
depicting locking of the spring holder 218 with the housing 102, according to an embodiment
of the present disclosure. Referring to Figure 4 and Figure 5, for locking the spring holder
218, the housing 102 may include a pair of stoppers 402 formed on the inner surface. Further,
7
9
the spring holder 218 may include a pair of arms 404 adapted to engage with the pair of
stoppers 402 for locking the spring holder 218 with the housing 102.
Further, the spring holder 218 may be engaged with the locking unit 220 as well. For
example, the spring holder 218 may be snap-locked with the locking unit 220. In an
5 embodiment, the needle guard 212, when being retracted, may be adapted to push the locking
unit 220 further into the spring holder 218 thereby unlocking the spring holder 218 from the
housing 102. Figure 6 illustrates a sectional view of the auto-injector assembly 100 depicting
unlocking of the spring holder 218 owing to movement of the needle guard 212, according to
an embodiment of the present disclosure.
10 The spring holder 218 is unlocked such that the plunger 222 is moved towards the
syringe assembly 202 for administering the drug into the injection site. In an embodiment, the
spring holder 218 may be adapted to unlock, releasing the dose delivery spring 216 from the
compressed state and pushing the plunger 222 towards the syringe assembly 202 based on a
compressive force of the dose delivery spring 216. Therefore, the plunger 222 may be adapted
15 to move towards the syringe assembly 202 when the spring holder 218 is unlocked. In the
locked state of the spring holder 218, the movement of the plunger 222 is restricted.
The plunger 222 may be engaged with the spring holder 218. In an embodiment, the
plunger 222 may include a plurality of threads formed on an outer surface. Further, the spring
holder 218 may include a nut (not shown) adapted to engage with the plurality of threads of
20 the plunger 222. The plunger 222 may be rotated into the nut for controlling the travelling
distance of the plunger 222 within the housing 102 to administer the drug into the injection
site based on the predetermined volume of the drug in the syringe assembly 202.
In another embodiment, the plunger 222 may include a plurality of threads formed on
an inner surface. Further, the spring holder 218 may include a shaft 224 adapted to engage
25 with the plurality of threads of the plunger 222. The plunger 222 may be adapted to rotate into
the shaft 224 for controlling the travelling distance of the plunger 222 within the housing 102
to administer the drug.
Therefore, a position of engagement of the plunger 222 with the spring holder 218 may
be adapted to change for controlling a travelling distance of the plunger 222 within the housing
30 102 based on the predetermined volume of the drug in the syringe assembly 202.
Figure 7 A illustrates a sectional view of the auto-injector assembly 100 depicting
position of constituent components in an initial state, i.e., before the needle guard 212 is
pressed on the injection site, according to an embodiment of the present disclosure. Further,
Figure 7B illustrates a sectional view of the auto-injector assembly 100 depicting position of
8
10
constituent components after drug is administered, according to an embodiment of the present
disclosure. As illustrated, the plunger 222 along with the spring holder 218 moves towards
the syringe assembly 202 to push the drug through the needle 406 into the injection site.
In an embodiment, the auto-injector assembly 100 may include a provision to ensure
5 that the device is not reused. Particularly, the engagement of the needle guard 212 and the
syringe holder 210 during the retraction and extension is such that the needle guard 212 is
locked with the syringe holder 210, ensuring to restrict further movement of the needle guard
212. Figure SA illustrates positioning of the needle guard 212 with respect to the syringe
holder 210 in the initial state, according to an embodiment of the present disclosure. The
10 syringe holder 210 may include a lock portion 802 formed on an outer surface. Further, the
needle guard 212 may include, but is not limited to, a longitudinal groove 804 adapted to
receive the lock portion 802 of the syringe holder 210.
The lock portion 802 may be adapted to travel along the longitudinal groove 804 for
accommodating relative movement of the needle guard 212 with respect to the syringe holder
15 210 when the needle guard 212 retracts into the housing 102. Further, the needle guard 212
may include a longitudinal slot 806 formed adjacent to the longitudinal groove 804. The
longitudinal slot 806 may be adapted to accommodate return travel of the lock portion 802
when the needle guard 212 is moving back to the original position after administering of the
drug.
20 Figure 8B illustrates positioning of the needle guard 212 with respect to the syringe
holder 210 after the drug is administered, according to an embodiment of the present
disclosure. As illustrated, the longitudinal slot 806 may include a stopper slot 808 that is
adapted to hold the lock portion 802 at the end of return travel, restricting further movement
of the needle guard 212 once the drug is administered. This provision of the auto-injector
25 assembly 100 acts as a safety feature to avoid needle stick injuries, for example, after the
disposal of the auto-injector assembly 100.
In an embodiment, the auto-injector assembly 100 may include a viewing slot 112
formed on the housing 102 to view the movement of the plunger 222 from outside. Therefore,
the user can inspect right usage of the auto-injector assembly 100 from the outside.
30 Figure 9 illustrates an example depicting usage of the auto-injector assembly 100 by a
user, according to an embodiment of the present disclosure. As shown, the cap 208 is removed.
The auto-injector assembly 100 is then positioned on an injection site on the patient and held
there for a predefined time duration. The auto-injector assembly 100 is activated by pressing
the needle guard 212 on the injection site. The pressing of the needle guard 212 may activate
9
11
needle insertion and dose dispensing with one action by the patient. Particularly, after
removing the cap 208, the user would press the proximal end 104 of the auto-injector assembly
100, i.e., the extended portion of the needle guard 212 on to the injection site. Once the drug
is delivered, used pens may be disposed in a sharps collector.
5 As would be gathered, the auto-injector assembly 100 of the present disclosure offers a
comprehensive and effective approach for delivering drugs in varying volumes into the
patient's body. In operation, the user removes the cap 208 along with the needle shield 408,
before positioning the auto-injector assembly 100 on the injection site. The needle guard 212
is then pressed on the injection site. Consequently, the needle guard 212 is retracted into the
10 housing 102, pushing the locking unit 220 and unlocking the spring holder 218. Consequently,
owing to the expansion of the dose delivery spring 216, the spring holder 218 along with the
plunger 222 moves towards the syringe assembly 202 to push the drug into the injection site
through the needle 406. Further, the needle guard 212 while reaching the original position,
due to the expansion of the needle guard spring 214, locks with the syringe holder 210,
15 restricting any further movement.
Once the delivery of drug is complete and the auto-injector assembly 100 is removed,
the needle guard 212 springs back and returns to its initial position covering the needle 406.
This protects the user from needle stick injury.
Therefore, the auto-injector assembly 100 is a drug delivery mechanism that can be used
20 with various kinds of drugs requiring to be delivered to the patient through a prefilled syringe
or a cartridge. The construction of the auto-injector assembly 100 is such that only one such
auto-injector assembly 100 can be used for different injection requirements by varying the
operating settings.
The plunger 222 can be engaged at different positions with the spring holder 218, for
25 example, through the nut or the shaft 224, based on different volumes of the drug to be
administer by the auto-injector assembly 100. Further, the spring holder 218 is locked with
the housing 102 through the engagement of the arms 404 and the stoppers 402. Therefore, the
spring holder 218 and the plunger 222 cannot move unless being unlocked by the needle guard
212. Moreover, once the drug is administered, the needle guard 212 locks with the syringe
30 holder 210 to ensure that the auto-injector assembly 100 is not reused.
Owing to the same device being used for different drug volume requirements, this would
significantly reduce manufacturing cost and inconvenience for a manufacturer. Further, an
overall operational cost of the auto-injector assembly 100 is also reduced. Further, handling
and maintenance of multiple auto-injectors, as is the case in the existing techniques, are
10
12
significantly reduced. Therefore, the auto-injector assembly 100 of the present disclosure is
easy to use, cost-effective, compact, and operation-effective, and offers an ease of
manufacturing, an ease of maintenance, and an ease of operation.
The auto-injector assembly 100 of the present disclosure may be used for delivering
5 different therapeutic compounds, such as drugs and biologics, including but not limited to,
antibodies, antisense, RNA interference, gene therapy, primary and embryonic stem cells,
vaccines, and combinations thereof. For instance, the embodiments described herein may be
utilized in combination with known monoclonal antibodies including, but not limited to,
Abciximab, Abituzumab, Abrilumab, Actoxumab, Adalimumab, Adecatumumab,
10 Aducanumab, Afasevikumab, Afelimomab, Afutuzumab, Alacizumab pegol, ALD518,
ALD403, Alemtuzumab, Alirocumab, Altumomab pentetate, Amatuximab, AMG 334,
Anatumomab mafenatox, Anetumab ravtansine, Anifrolumab, Anrukinzumab, Apolizumab,
Arcitumomab, Ascrinvacumab, Aselizumab, Atezolizumab, Atinumab, Atlizumab,
Atorolimumab, Avelumab, Bapineuzumab, Basiliximab, Bavituximab, Bectumomab,
15 Begelomab, Belimumab, Benralizumab, Bertilimumab, Besilesomab, Bevacizumab,
Bezlotoxumab, Biciromab, Bimagrumab, Bimekizumab, Bivatuzumab mertansine,
Bleselumab, Blinatumomab, Blontuvetmab, Blosozumab, Bococizumab, Brazikumab,
Brentuximab vedotin, Briakinumab, Brodalumab, Brolucizumab, Brontictuzumab,
Burosumab, Cabiralizumab, Canakinumab, Cantuzumab mertansine, Cantuzumab ravtansine,
20 Caplacizumab, Capromab pendetide, Casirivimab, Carlumab, Carotuximab, Catumaxomab,
cBR96-doxorubicin immunoconjugate, Cedelizumab, Cergutuzumab amunaleukin,
Certolizumab pegol, Cetuximab, Citatuzumab bogatox, Cixutumumab, Clazakizumab,
Clenoliximab, Clivatuzumab tetraxetan, Codrituzumab, Coltuximab ravtansine,
25
Conatumumab, Concizumab,
Daclizumab, Dalotuzumab,
CR6261, Crenezumab, Crotedumab,
Dapirolizumab pegol, Daratumumab,
Dacetuzumab,
Dectrekumab,
Demcizumab, Denintuzumab mafodotin, Denosumab, Depatuxizumab mafodotin,
Derlotuximab biotin, Detumomab, Dinutuximab, Diridavumab, Domagrozumab,
Dorlimomab aritox, Drozitumab, Duligotumab, Dupilumab, Durvalumab, Dusigitumab,
Ecromeximab, Eculizumab, Edobacomab, Edrecolomab, Efalizumab, Efungumab,
30 Eldelumab, Elgemtumab, Elotuzumab, Elsilimomab, Emactuzumab, Emibetuzumab,
Emicizumab, Enavatuzumab, Enfortumab vedotin, Enlimomab pegol, Enoblituzumab,
Enokizumab, Enoticumab, Ensituximab, Epitumomab cituxetan, Epratuzumab, Erenumab,
Erlizumab, Ertumaxomab, Etaracizumab, Etrolizumab, Evinacumab, Evolocumab,
Exbivirumab, Fanolesomab, Faralimomab, Farletuzumab, Fasinumab, FBTA05, Felvizumab,
11
13
Fezakinumab, Fibatuzumab, Ficlatuzumab, Figitumumab, Firivumab, Flanvotumab,
Fletikumab, Fontolizumab, Foralumab, Foravirumab, Fresolimumab, Fulranumab,
Futuximab, Galcanezumab, Galiximab, Ganitumab, Gantenerumab, Gavilimomab,
Gemtuzumab ozogam1cm, Gevokizumab, Girentuximab, Glembatumumab vedotin,
5 Golimumab, Gomiliximab, Guselkumab, Ibalizumab, lbritumomab tiuxetan, Icrucumab,
Idarucizumab, Igovomab, IMA-638, IMAB362, Imalumab, Imciromab, Imdevimab,
Imgatuzumab, Inclacumab, Indatuximab ravtansine, Indusatumab vedotin, Inebilizumab,
Infliximab, Inolimomab, Inotuzumab ozogamicin, Intetumumab, Ipilimumab, Iratumumab,
Isatuximab, ltolizumab, Ixekizumab, Keliximab, Labetuzumab, Lambrolizumab,
10 Lampalizumab, Lanadelumab, Landogrozumab, Laprituximab emtansine, LBR-
101/PF0442g7429, Lebrikizumab, Lemalesomab, Lendalizumab, Lenzilumab,
Lerdelimumab, Lexatumumab, Libivirumab, Lifastuzumab vedotin, Ligelizumab, Lilotomab
satetraxetan, Lintuzumab, Lirilumab, Lodelcizumab, Lokivetmab, Lorvotuzumab mertansine,
Lucatumumab, Lulizumab pegol, Lumiliximab, Lumretuzumab, L Y29517 42,
15 Mapatumumab, Margetuximab, Maslimomab, Matuzumab, Mavrilimumab, Mepolizumab,
Metelimumab, Milatuzumab, Minretumomab, Mirvetuximab soravtansine, Mitumomab,
Mogamulizumab, Monalizumab, Morolimumab, Motavizumab, Moxetumomab pasudotox,
Muromonab-CD3, Nacolomab tafenatox, Nam ilumab, Naptumomab estafenatox,
Naratuximab emtansine, Narnatumab, Natalizumab, Navicixizumab, Navivumab,
20 Nebacumab, Necitumumab, Nemolizumab, Nerelimomab, Nesvacumab, Nimotuzumab,
Nivolumab, Nofetumomab merpentan, Obiltoxaximab, Obinutuzumab, Ocaratuzumab,
Ocrelizumab, Odulimomab, Ofatumumab, Olaratumab, Olokizumab, Omalizumab,
Onartuzumab, Ontuxizumab, Opicinumab, Oportuzumab monatox, Oregovomab, Orticumab,
Otelixizumab, Otlertuzumab, Oxelumab, Ozanezumab, Ozoralizumab, Pagibaximab,
25 Palivizumab, Pamrevlumab, Panitumumab, Pankomab, Panobacumab, Parsatuzumab,
Pascolizumab, Pasotuxizumab, Pateclizumab, Patritumab, Pembrolizumab, Pemtumomab,
Perakizumab, Pertuzumab, Pexelizumab, Pidilizumab, Pinatuzumab vedotin, Pintumomab,
Placulumab, Plozalizumab, Pogalizumab, Polatuzumab vedotin, Ponezumab, Prezalizumab,
Priliximab, Pritoxaximab, Pritumumab, PRO 140, Quilizumab, Racotumomab, Radretumab,
30 Rafivirumab, Ralpancizumab, Ramucirumab, Ranibizumab, Raxibacumab, Refanezumab,
Regavirumab, Reslizumab, Rilotumumab, Rinucumab, Risankizumab, Rituximab,
Rivabazumab pegol, Robatumumab, Roledumab, Romosozumab, Rontalizumab,
Rovalpituzumab tesirine, Rovelizumab, Ruplizumab, Sacituzumab govitecan, Samalizumab,
Sapelizumab, Sarilumab, Satumomab pendetide, Secukinumab, Seribantumab, Setoxaximab,
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14
Sevirumab, SGN-CD19A, SGN-CD33A, Sibrotuzumab, Sifalimumab, Siltuximab,
Simtuzumab, Siplizumab, Sirukumab, Sofituzumab vedotin, Solanezumab, Solitomab,
Sonepcizumab, Sontuzumab, Stamulumab, Sulesomab, Suvizumab, Tabalumab,
Tacatuzumab tetraxetan, Tadocizumab, Talizumab, Tamtuvetmab, Tanezumab,
5 Taplitumomab paptox, Tarextumab, Tefibazumab, Telimomab aritox, Tenatumomab,
Teneliximab, Teplizumab, Teprotumumab, Tesidolumab, Tetulomab, Tezepelumab,
TGN1412, Ticilimumab, Tigatuzumab, Tildrakizumab, Timolumab, Tisotumab vedotin,
TNX-650, Tocilizumab, Toralizumab, Tosatoxumab, Tositumomab, Tovetumab,
Tralokinumab, Trastuzumab, Trastuzumab emtansine, TRBS07, Tregalizumab,
10 Tremelimumab, Trevogrumab, Tucotuzumab celmoleukin, Tuvirumab, Ublituximab,
Ulocuplumab, Urelumab, Urtoxazumab, Ustekinumab, Utomilumab, Vadastuximab talirine,
V andortuzumab vedotin, V antictumab, V anucizumab, V apaliximab, V arlilumab,
V atelizumab, V edolizumab, V eltuzumab, V epalimomab, V esencumab, Visilizumab,
Vobarilizumab, Volociximab, Vorsetuzumab mafodotin, Votumumab, Xentuzumab,
15 Zalutumumab, Zanolimumab, Zatuximab, Ziralimumab, and Zolimomab aritox or
combinations thereof.
While specific language has been used to describe the present subject matter, any
limitations arising on account thereto, are not intended. As would be apparent to a person in
the art, various working modifications may be made to the method in order to implement the
20 inventive concept as taught herein. The drawings and the foregoing description give examples
of embodiments. Those skilled in the art will appreciate that one or more of the described
elements may well be combined into a single functional element. Alternatively, certain
elements may be split into multiple functional elements. Elements from one embodiment may
be added to another embodiment.

we claim.
1. An auto-injector assembly (100) comprising:
a housing (102) having a proximal end (104) and a distal end (106);
a syringe assembly (202) disposed adjacent to the proximal end (104) of the
housing (102) and adapted to store a predetermined volume of a drug to be administered
through a needle (406);
a needle guard (212) disposed to surround the syringe assembly (202) such that a
portion of the needle guard (212) is adapted to extend out of the housing (102) in an
10 initial state and to retract into the housing (102) when the portion is pressed on to an
injection site;
a spring holder (218) disposed adjacent to the distal end (106) of the housing (102)
and adapted to hold a dose delivery spring (216) in a compressed state;
a locking unit (220) disposed inside the spring holder (218) and adapted to keep
15 the spring holder (218) in a locked state with the housing (102); and
a plunger (222) engaged with the spring holder (218) and adapted to move towards
the syringe assembly (202) when the spring holder (218) is unlocked, wherein a position
of engagement of the plunger (222) with the spring holder (218) is adapted to change
for controlling a travelling distance of the plunger (222) within the housing ( 1 02) based
20 on the predetermined volume of the drug in the syringe assembly (202),
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30
wherein the needle guard (212), when being retracted, is adapted to push the
locking unit (220) further into the spring holder (218), unlocking the spring holder (218)
from the housing (102) such that the plunger (222) is moved towards the syringe
assembly (202) for administering the drug into the injection site.
2. The auto-injector assembly (100) as claimed in claim 1, wherein the needle guard (212)
is adapted to be pressed against the injection site to extend the needle ( 406) of the
syringe assembly (202) for being inserted into the injection site and to return to an
original position when the drug is administered.
3. The auto-injector assembly (100) as claimed in claim 1, comprising
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16
a syringe holder (210) adapted to support the syringe assembly (202) within the
housing (102); and
a needle guard spring (214) adapted to be disposed between an inner surface of
the housing (102) and an outer surface of the needle guard (212), wherein the needle
5 guard spring (214) is adapted to support the movement of the needle guard (212) within
the housing (102) for administering the drug.
4.
10
5.
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20
6.
The auto-injector as claimed in claim 1, comprising:
the housing (102) having a pair of stoppers (402) formed on an inner surface; and
the spring holder (218) comprising a pair of arms (404) adapted to engage with
the pair of stoppers (404) for locking the spring holder (218) with the housing (102),
restricting the movement of the plunger (222).
The auto-injector as claimed in claim 1, comprising:
the plunger (222) having a plurality of threads formed on an outer surface; and
the spring holder (218) comprising a nut adapted to engage with the plurality of
threads of the plunger (222), wherein the plunger (222) is rotated into the nut for
controlling the travelling distance of the plunger (222) within the housing (102) to
administer the drug into the injection site based on the predetermined volume of the
drug in the syringe assembly (202).
The auto-injector as claimed in claim 1, comprising:
the plunger (222) having a plurality of threads formed on an inner surface; and
the spring holder (218) comprising a shaft (224) adapted to engage with the
plurality of threads of the plunger (222), wherein the plunger (222) is rotated into the
25 shaft (224) for controlling the travelling distance of the plunger (222) within the housing
(102) to administer the drug into the injection site based on the predetermined volume
of the drug in the syringe assembly (202).
7. The auto-injector assembly (100) as claimed in claim 1, wherein the spring holder (218)
is adapted to unlock, releasing the dose delivery spring (216) from the compressed state
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8.
5
10
9.
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20
and pushing the plunger (222) towards the synnge assembly (202) based on a
compressive force of the dose delivery spring (216).
The auto-injector assembly (100) as claimed in claim 1, comprising:
a needle shield ( 408) adapted to encapsulate the needle ( 406); and
a cap (208) fixed with the needle shield ( 408) and adapted to close the proximal
end (104) of the housing (102) when not in use,
wherein the cap (208) and the needle shield ( 408) are adapted to be removed
before pressing the needle guard (212) against the injection site for administering the
drug.
The auto-injector assembly (100) as claimed in claim 3, comprising:
and
the syringe holder (210) having a lock portion (802) formed on an outer surface;
the needle guard (212) comprising:
a longitudinal groove (804) adapted to receive the lock portion (802) of the
syringe holder (210), wherein the lock portion (802) is adapted to travel along the
longitudinal groove (804) for accommodating relative movement of the needle
guard (212) with respect to the syringe holder (210) when the needle guard (212)
retracts into the housing (102); and
a longitudinal slot (806) formed adjacent to the longitudinal groove (804)
and adapted to accommodate return travel of the lock portion (802) when the
needle guard (212) is moving back to the original position after administering of
the drug, wherein the longitudinal slot (806) comprising a stopper slot (808) that
is adapted to hold the lock portion (802) at the end of return travel, restricting
25 further movement of the needle guard (212) once the drug is administered.
30
10. The auto-injector assembly (100) as claimed in claim 1, comprising a viewing slot (112)
formed on the housing (102) to view the movement of the plunger (222) from outside.