Field of the Invention:-
The present invention relates to a pre-loaded syringe for storage and delivery of viscous, sticky and chemically reactive drugs. Particularly, it relates to a pre-loaded syringe for storage and delivery of viscous, sticky and chemically reactive drugs, for example injectable contraceptives containing dimethyl sulfoxide [DMSO] required for injecting into lumen of vas deferens.
Background of the Invention:-
The vas deferens is a tubular structure linking the testes of the male to the ejaculatory duct. The scrotum of the male contains two testes and each testes has an independent vas deferens. Each vas deferens has a muscular wall and a central lumen which runs along the axis of the vas deferens. The spermatic fluid contains sperms flowing along lumen of the vas deferens being transported from the testes to the ejaculatory duct. In cross-section, the vas deferens has typically an outer diameter of about 2.5 mm or more and the lumen has a diameter of about 0.6 mm. The vas deferens is, therefore, a thick walled tube with very narrow lumen. The lumen will stretch when an injection needle is inserted into the lumen.
For the contraceptive application as well as for the diagnostic tests, there is a need to inject drugs into the lumen of the vas deferens. For this operation, the injection needle needs to be so handled that it penetrates the skin of the scrotum, penetrates the muscular wall of the vas deferens, and correctly and accurately enters the lumen of the vas deferens so that the drug is delivered into the lumen without puncturing the walls of the vas deferens. This procedure is termed as "percutaneous injection" which implies injection through the skin without directly seeing the structure which in the present case is very narrow lumen of vas deferens.
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The alternative to the percutaneous procedure is to cut open the skin with a scalpel, expose the vas deferens and inject the drug under direct visualization of the vas deferens. The "direct vision method" being a surgical procedure needs to be replaced by a percutaneous procedure.
The vas deferens is within the scrotal sac and is not visible. Being somewhat firmer than the skin tissue the vas can be felt by gripping the skin between two fingers but its diameter cannot be judged accurately because the skin thickness is about 2.5 mm or more.
Further, aligning the needle to be precisely over the central part of the vas deferens is subject to errors. Therefore, after the tip of the needle is made to penetrate the scrotal skin, the tip may deviate from the axis of the lumen of the vas deferens if the scrotal skin thickness and the diameter of the vas deferens are not known accurately. Under such circumstances, it is also possible that one may also miss the vas deferens completely. More commonly, the needle may also penetrate some part of the wall of the vas deferens, but may not enter the lumen. Further, if the needle does not align properly with the lumen, the needle tip may enter the lumen and then puncture through the opposite wall of the vas deferens.
The above problem is further enhanced due to very viscous and sticky nature of the injectable contraceptive which comprises dimethyl sulfoxide [DMSO] in higher amount as main ingredient of the formulation.
As the injectable contraceptive drug comprising DMSO is very viscous and sticky, it requires special art to load the syringe [the injection or drug delivery system]. Further due to its viscous and sticky nature, it also requires very high pressure for loading the syringe [the injection or
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drug delivery system]. Still furthermore due to its viscous and sticky nature, it also requires very high pressure for deloading the syringe [the injection or drug delivery system] for injecting the contraceptive drug into lumen of vas deferens.
Further, as diameter of lumen of vas deferens is very small, about 0.6 mm, the syringe [the injection or drug delivery system] is required to have needle of very small diameter at least less than about 0.6 mm, which further enhances the requirement of very high pressure for injecting very viscous and sticky contraceptive drug into lumen of vas deferens.
Accordingly, due to very viscous and sticky nature of the injectable contraceptive drug comprising DMSO, the surgeon needs to know special art to load the syringe, and needs to have capability to generate very high pressure required for loading the syringe and capability to generate very high pressure required for deloading the syringe for injecting the contraceptive drug into very narrow lumen of vas deferens.
It has been observed that the surgeons injecting injectable contraceptive drug comprising DMSO into very narrow lumen of vas deferens generally cannot load the syringe with viscous and sticky drug and also cannot deload the drug for injecting into very narrow lumen of vas deferens, particularly during the percutaneous injection wherein the drug is required to be injected into very narrow lumen of the vas deferens while properly adjusting and handling the injection needle in such a manner that it first penetrates the skin of the scrotum, then penetrates the muscular wall of the vas deferens, and then correctly and accurately enters the narrow lumen of the vas deferens so that the drug is delivered only into the lumen without puncturing the walls of the vas deferens, that is the surgeon is required to inject the viscous and sticky drug without
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directly seeing the structure which in the present case is lumen of vas deferens, that's too under very high pressure.
It has been further observed that presently available injection syringes made of glass material cannot withstand the pressure required for loading and deloading the viscous and sticky injectable contraceptive drug comprising DMSO, particularly when the drug has to be injected in very narrow lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection under high pressure.
Accordingly, there is a need to have pre-loaded syringe loaded with viscous and sticky injectable contraceptive drug comprising DMSO and suitable to withstand the pressure required for loading and deloading the viscous and sticky injectable contraceptive drug comprising DMSO, particularly when the drug has to be injected into very narrow lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection.
Further, the injectable contraceptive drug comprising DMSO is also very reactive, which generally reacts with all plastic and rubber materials. Therefore, the drug cannot be left in contact with any plastic and rubber material of a pre-loaded syringe for longer duration during its storage and transportation to hospitals for onward use by surgeons for injecting the drug into lumen of vas deferens.
Accordingly, there is a need to have pre-loaded syringe loaded with viscous and sticky injectable contraceptive drug comprising DMSO which is primarily made of glass or a material which does not come in contact with the drug during its storage and transportation. If at all the syringe comprises any other material, then the same should not come in direct contact with the drug during its storage and transportation.
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As stated herein above, the presently available injection syringes made of glass material cannot withstand the pressure required for loading and deloading the viscous and sticky injectable contraceptive drug comprising DMSO, particularly when it has to be injected in very narrow lumen of vas deferens, more particularly when it has to be injected during the percutaneous injection under high pressure. Furthermore, the presently available injection syringes comprise plunger or part of the plunger, and/or needle holding means made of plastic or rubber material, which as stated herein above reacts with reactive injectable contraceptive drug comprising DMSO.
Therefore, it has been observed that presently available syringes [injection or drug delivery systems] are not suitable for loading and deloading the viscous, sticky and reactive injectable contraceptive drug comprising DMSO, particularly when the drug has to be injected into very narrow lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection under high pressure without having high probability of breakage of syringe and reaction of drug with plunger or part of plunger and/or needle holding means which are made of plastic or rubber material.
Further, it has been observed that loading of presently available syringes by usual means of suction is not possible due to highly viscous and sticky nature of the drug, which has to enter, during the suction, through very narrow bore of the needle.
Therefore, need of pre-loaded syringes with viscous and sticky injectable contraceptive drug comprising DMSO is unavoidable, because it will at least avoid requirement of special technique and high pressure to
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load the syringe with the drug before injecting the drug into lumen of vas deferens.
Objects of the Invention:-
Main object of the present invention is to provide a pre-loaded syringe loaded with highly viscous, sticky and reactive drug, for example injectable contraceptive drug comprising DMSO which is suitable to withstand the pressure required for loading and deloading the viscous and sticky drug, particularly when the drug has to be injected into very narrow lumen, for example in the lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection.
Another object of the present invention is to provide a pre-loaded syringe loaded with highly viscous, sticky and reactive drug, which is primarily made of glass which does not react with reactive drug, and if at all the syringe comprises any other material, then such another material does not come in direct contact with the drug during its storage and transportation.
Still another object of the present invention is to provide a pre
loaded syringe loaded with highly viscous, sticky and reactive drug, which
is suitable for deloading the viscous, sticky and reactive drug, particularly
when the drug has to be injected into very narrow lumen of vas deferens,
more particularly when the drug has to be injected during the
percutaneous injection under high pressure without having any
probability of breakage of syringe and reaction of drug with any part of the
syringe.
Yet another object of the present invention is to provide a pre-loaded syringe loaded with highly viscous, sticky and reactive drug meaning
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thereby avoids loading of syringe with viscous, sticky and reactive drug by usual means of suction.
Other objects and advantages of the present invention will be apparent from the following description of the present invention when read in conjunction with accompanying drawings, which are not intended to limit the scope of present invention.
Brief Description of the Accompanying Figures:-
Figure 1 illustrates body of the syringe [injection or drug delivery system] provided with holding means and closing means at both the opposite ends of the body of the syringe in accordance with one of the preferred embodiments of the present invention.
Figure 2 illustrates plunger [piston] of the syringe [injection or drug delivery system] provided with specially designed front end in accordance with one of the preferred embodiments of the present invention.
Figure 3 illustrates additional retaining means for retaining the closing means provided on one end of body of the syringe [injection or drug delivery system] in accordance with one of the preferred embodiments of the present invention.
Figure 4 illustrates additional retaining means for retaining the closing means provided on another end of body of the syringe [injection or drug delivery system] in accordance with one of the preferred embodiments of the present invention.
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Figure 5 illustrates one of the preferred embodiments of the rear closing means of the syringe [injection or drug delivery system] in accordance with present invention.
Detailed Description and Preferred Embodiments of the Invention
The present invention relates to a pre-loaded syringe for storage and delivery of viscous, sticky and chemically reactive drugs. Particularly, it relates to a pre-loaded syringe for storage and delivery of viscous, sticky and chemically reactive drugs, for example injectable contraceptives containing dimethyl sulfoxide [DMSO] required for injecting into lumen of vas deferens.
In accordance with one embodiment, the present invention relates to a pre-loaded syringe loaded with highly viscous, sticky and reactive drug, for example injectable contraceptive drug comprising DMSO which is capable of withstanding the high pressure required for loading and deloading the viscous and sticky drug, particularly when the drug has to be injected into very narrow lumen, for example in the lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection under high pressure.
In accordance with another embodiment, the present invention relates to a pre-loaded syringe loaded with highly viscous, sticky and reactive drug, which is made of glass and inert materials thereby avoids any reaction with reactive drug, and if at all the syringe comprises any other material, then such another material does not come in direct contact with the drug during its storage and transportation.
In accordance with still another embodiment, the present invention relates to a pre-loaded syringe loaded with highly viscous, sticky and
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reactive drug, which is capable of deloading the viscous, sticky and reactive drug, particularly when the drug has to be injected into very narrow lumen of vas deferens, more particularly when the drug has to be injected during the percutaneous injection under high pressure without any probability of breakage of syringe, and is suitable for storage and delivery of the stored drug without any probability of any reaction with any part of the syringe.
In accordance with yet another embodiment, the present invention relates to a pre-loaded syringe pre-loaded with highly viscous, sticky and reactive drug meaning thereby avoids loading of syringe with viscous, sticky and reactive drug by usual means of suction and provides comfort and convenience to the surgeons.
Accordingly, the present invention relates to a syringe [injection or drug delivery system] suitable for pre-loading with highly viscous, sticky and reactive drug and for withstanding higher pressure required for loading and deloading the viscous and sticky drug comprising a syringe body having a lumen provided with holding means and closing means at both the opposite ends of the syringe body of the syringe, and a plunger, also known as piston of the syringe provided with specially designed front end.
In one of the preferred embodiments of the present invention, the closing means provided at one end of the syringe body of the syringe is provided with additional retaining means for retaining the closing means.
In another preferred embodiment of the present invention, the closing means provided at another end of the syringe body of the syringe is provided with additional retaining means for retaining the closing means.
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Accordingly, present invention provides a drug delivery system suitable for pre-loading with highly viscous, sticky and reactive drug and for withstanding higher pressure required for loading and deloading the viscous and sticky drug comprising a syringe body 1 having a lumen 2 therethrough, characterized in that said syringe body 1 is provided with a front holding means 3 at its front end 4 for holding the front closing means 5 for closing the front opening 6 of said syringe body 1 and a rear holding means 7 at its rear end 8 for holding the rear closing means 9 for closing the rear opening 10 of the syringe body, and a plunger 11 capable of fitting into said lumen 2 of said syringe body 1.
In accordance with present invention, the plunger is provided with a cap 12 made from an inert material at its front end 13.
In accordance with present invention, the front end 4 of the syringe body 1 extends into a conical shaped projection 14 which is capable of holding the front closing means 5 for closing the front opening 6 of the syringe body 1 during the storage and transportation of the drug.
In accordance with one of the preferred embodiments of the present invention, the front closing means 5 for closing the front opening 6 of the syringe body 1 is additionally provided with a front retaining means 15 which is capable of retaining the front closing means 5 in its position during the storage and transportation of the drug.
In accordance with another preferred embodiment of the present invention, the rear closing means 9 for closing the rear opening 10 of the syringe body 1 is additionally provided with a rear retaining means 16 which is capable of retaining the rear closing means 9 in its position during the storage and transportation of the drug.
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In accordance with one of the preferred embodiments of the present invention, the rear closing means 9 is conical shaped [Figure 5].
In accordance with one of the preferred embodiments of the present invention, the front holding means 3 is slightly inclined towards projection 14 and itself acts as securing means for securing the front closing means 5.
In accordance with one of the preferred embodiments of the present invention, the projection 14 on the front end 4 of the syringe 1 is provided with micro groves for air tight fitting of the front closing means 5 during storage and transportation of the drug and of needle [not shown in figures] during the delivery of stored drug.
The projection 14 provided with microgrooves on the front end 4 of the syringe 1 is preferably conical in shape which has the advantage of providing leak proof and air tight locking between front closing means 5 during storage and transportation of the drug and needle [not shown in figures] during the delivery of stored drug.
In accordance with one of the preferred embodiments of the present invention, the lumen 2 of the syringe body 1 is very narrow which has been surprisingly found to have advantage of requiring very low pressure to deliver the drug while deloading the syringe.
As in presently disclosed syringe the needle [not shown in figures] fits onto the projection 14, it does not go into the lumen of the syringe body meaning thereby there is no probability of flow resistance which is caused in conventional syringes known in the prior art.
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In accordance with one of the preferred embodiment of the present invention, the front end 13 of the plunger 11 is provided with a cap 12 made of inert material, preferably of teflon, which has been found to have advantage of being highly inert with injectable drugs and air tight sealing between syringe body and plunger meaning thereby overcomes problems of reaction between syringe material and stored drug, and probability of leakage drug, particularly viscous drug during deloading the syringe and probability of drug coming in contact with environmental gases during deloading of drug.
Accordingly, the stored drug does not come in contact with any reactive material such as plastic or rubber meaning thereby there is no probability of reaction of drug with material of presently disclosed syringe.
In accordance with another preferred embodiment of the present invention, the rear closing means 9 when it is conical shape [Figure 5] is provided with micro grooves and rear opening 10 of the syringe body 1 is also provided with micro grooves for have advantage of achieving air tight fitting of the rear closing means 9 in rear opening 10 of the syringe body 1 during storage and transportation of the drug.
It has been surprisingly observed that the microgrooves provided on front projection 14 are capable of avoiding use of luer lock which has probability of breakage and leakage during use of the conventional syringes.
It has also been observed that closing of rear end of the syringe body with presently disclosed rear closing means with or without additional rear retaining means avoids problem of placing the plunger during storage and transportation of the drug which will cause problems due to extended length of the syringe.
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It has also been observed that front holding means provided at front end of the syringe body and microgrooves provided on the front projection have advantage of securely and tightly holding the needle during delivery of drug meaning thereby overcomes problem of needle being coming out from its place and rendering the injection process useless and causing trauma to the subject.
Accordingly, it has been observed that presently disclosed syringe overcomes main drawbacks and limitations of the known prior art as described hereinabove.
It may be noted that the present invention has been described with reference to an injection system for injecting an injectable contraceptive drug comprising DMSO into lumen of vas deferens during the percutaneous injection. However, the persons skilled in the art can use the present system for injecting any drug or fluid into any tubular body having a lumen therethrough or into a tissue.
Therefore, in one of the embodiments, the present invention discloses an injection system for injecting any drug or fluid into any tubular body having a lumen therethrough or into a tissue of such body or any tissue of the subject.

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We Claim:
1. A drug delivery system suitable for pre-loading with highly viscous,
sticky and reactive drug and for withstanding higher pressure
required for loading and deloading the viscous and sticky drug
comprising a syringe body 1 having a lumen 2 therethrough,
characterized in that said syringe body 1 is provided with a front
holding means 3 at its front end 4 for holding the front closing
means 5 for closing the front opening 6 of said syringe body 1 and a
rear holding means 7 at its rear end 8 for holding the rear closing
means 9 for closing the rear opening 10 of the syringe body, and a
plunger 11 capable of fitting into said lumen 2 of said syringe body
2. A system as claimed in claim 1, wherein said plunger 11 is provided
with a cap 12 made from an inert material at its front end 13.
3. A system as claimed in claim 1 or 2, wherein said front end 4
extends into a conical shaped projection 14 capable of holding said
front closing means 5 for closing said front opening 6 during the
storage and transportation of the drug.
4. A system as claimed in any one of the preceding claims, wherein
said front closing means 5 for closing said front opening 6 is
additionally provided with a front retaining means 15 capable of
retaining said front closing means 5 in its position during the
storage and transportation of the drug.
5. A system as claimed in any one of the preceding claims, wherein
said rear closing means 9 for closing said rear opening 10 is
additionally provided with a rear retaining means 16 capable of
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retaining said rear closing means 9 in its position during the storage and transportation of the drug.
6. A system as claimed in any one of the preceding claims, wherein
said rear closing means 9 is conical shaped.
7. A system as claimed in any one of the preceding claims, wherein
said front holding means 3 is slightly inclined towards projection 14
and itself acts as securing means for securing said front closing
means 5.
8. A system as claimed in any one of the preceding claims, wherein
said projection 14 is provided with micro groves for air tight fitting
of said front closing means 5 during storage and transportation of
the drug and of needle during the delivery of stored drug.
9. A system as claimed in any one of the preceding claims, wherein
said projection 14 is preferably conical in shape.
10. A system as claimed in any one of the preceding claims, wherein
said lumen 2 is very narrow and capable of delivering the drug at
very low pressure.
11. A system as claimed in any one of the preceding claims, wherein
said needle fits onto said projection 14.
12. A system as claimed in any one of the preceding claims, wherein
said front end 13 is provided with a cap 12 made of inert material.
13. A system as claimed in any one of the preceding claims, wherein
said rear closing means 9 is provided with micro grooves and
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capable of forming air tight fitting with rear opening 10 during storage and transportation of the drug.
14. A system as claimed in any one of the preceding claims, wherein
said microgrooves provided on said front projection 14 are capable
of avoiding use of luer lock.
15. A drug delivery system substantially as herein described with
reference to and as illustrated in the accompanying figures.
14.

Dated this 6th day of November, 2006.

[Dr. Ramesh Kr. MEHTA]
Patent Attorney For the APPLICANTS
Mehta & Mehta Associates

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Pre-loaded Syringe for Storage and Delivery of Viscous, Sticky and Chemically Reactive Drugs
A drug delivery system is provided which is suitable for pre-loading with highly viscous, sticky and reactive drug and for withstanding higher pressure required for loading and deloading the viscous and sticky drug comprising a syringe body 1 having a lumen 2 therethrough, characterized in that said syringe body 1 is provided with a front holding means 3 at its front end 4 for holding the front closing means 5 for closing the front opening 6 of said syringe body 1 and a rear holding means 7 at its rear end 8 for holding the rear closing means 9 for closing the rear opening 10 of the syringe body, and a plunger 11 capable of fitting into said lumen 2 of said syringe body 1.