A retainer for a needle assembly of a retractable syringe that includes a plunger assembly and a barrel having a mounting member. The needle assembly includes a retractable needle, a needle hub, and a retainer. The retractable needle is engageable by the plunger assembly to facilitate retraction thereof. The needle hub is mountable to the mounting member of the barrel. The retainer includes a body and at least one retaining member that extends distally from the body. The retaining member includes an inwardly projecting lateral projection to engage the retractable needle and thereby prevent inadvertent proximal movement of said retractable needle prior to retraction. A retractable needle assembly includes the retainer, and a retractable syringe includes the retractable needle assembly including the retainer. A syringe kit includes a retractable syringe, a plurality of retractable needle assemblies, and a vial adapter.

A connector mountable to a syringe barrel has a proximal barrel-engaging portion, a distal luer fitment portion, and a fluid aperture therethrough. The barrel-engaging portion of the connector includes an axial ledge configured to abut the axial distal edge of a glass syringe barrel. The connector facilitates mounting a luer assembly to the barrel. The luer assembly may be a tip cap having a complementary luer fitment for connection to the luer fitment portion of the connector. The luer assembly may be a luer needle assembly having a complementary luer fitment for connection to the luer fitment portion of the connector. The connector and syringe may further include an immobile, compressible needle seal. The needle seal is adjacent to or engageable with the barrel-engaging portion of the connector. The syringe may be configured with a plunger capable of engaging a retractable needle.

A pneumatic retractable syringe has a plunger having an interior retraction lumen. The plunger and syringe barrel have cooperating locking elements so that the plunger is locked after use within the syringe barrel. After injection of medicament is completed, the needle is retracted into the lumen by compressed gas that is released from a gas cell within the syringe when the gas cell is ruptured just before the plunger reaches the end of its downstream path of travel.

A system for injecting includes a cartridge body defining a proximal opening and a distal needle interface. The system also includes a plunger member defining a plunger interior and configured to be manually manipulated to insert a stopper member relative to the cartridge body. The plunger member includes a needle retention feature disposed in the plunger interior, an energy-storage member disposed in the plunger interior, and an energy-storage member latching member disposed in the plunger interior. The system further includes a needle hub assembly coupled to the distal needle interface of the cartridge body. The needle assembly includes a needle having a needle proximal end feature, a hub, and a needle latching member configured to couple the needle to the hub. The needle is retractable into plunger interior upon manipulation of the plunger member to actuate the energy-storage member latching member.

One embodiment is directed to a system for injecting, comprising a syringe body defining an interior medicine chamber; a stopper member configured to be inserted into the interior medicine chamber to contain medicine within the medicine chamber; a plunger member configured to be manually manipulated to insert the stopper member relative to the syringe body; a needle having proximal and distal ends, the proximal end comprising an anchoring geometry configured to be at least partially penetrated into the stopper member such that upon retraction of the stopper member, the needle is pulled proximally along with the stopper to be at least partially contained within the interior medicine chamber; and an energy-storing member operatively coupled between the stopper member and the syringe body, the energy-storing member configured to facilitate retraction of the stopper member relative to the syringe body.

A low retraction activation force plunger sub-assembly for an automatic injector includes: a plunger outer having one or more engagement prongs, a plunger inner having a shoulder, and a plunger biasing member retained in a first energized state between said plunger outer and plunger inner when the engagement prongs of the plunger outer are releasably engaged with the shoulder of the plunger inner. An automatic injector includes a housing, an activation mechanism, an actuation mechanism, and a syringe cartridge having the plunger sub-assembly and a needle assembly, wherein the actuation mechanism includes comprises an actuation biasing member residing in an initial energized state substantially within an upper portion of an actuation pill. A method of assembling the automatic injector includes the steps of: assembling the plunger sub-assembly and inserting the plunger sub-assembly into the housing such that a proximal end of the plunger sub-assembly contacts the actuation pill.

One embodiment is directed to a system for injecting, comprising a syringe body defining an interior medicine chamber; a stopper member configured to be inserted into the interior medicine chamber to contain medicine within the medicine chamber; a plunger member configured to be manually manipulated to insert the stopper member relative to the syringe body; and a needle having proximal and distal ends, the proximal end comprising an anchoring geometry configured to be at least partially inserted into the stopper member such that upon retraction of the stopper member, the needle is pulled proximally along with the stopper to be at least partially contained within the interior medicine chamber.

A replaceable needle assembly is provided for a retractable, prefilled syringe comprising a barrel having a mounting member and a plunger, whereby the retractable needle can be replaced by a user without affecting the retraction mechanism. The replaceable needle assembly comprises a needle fitted to a retractable needle mount and a needle retainer. The needle mount is removably, screw-threadedly mountable to the mounting member of the barrel. The needle retainer comprises a plurality of fingers that releasably engage the retractable needle to thereby prevent inadvertent retraction of the retractable needle before engagement by the plunger. The plunger comprises a plunger seal comprising an outer member and an inner member that engages the needle for spring-driven retraction. At the end of retraction, a lock is formed between the plunger and barrel to prevent re-use of the syringe.

The present embodiments provide for a syringe and a retraction plunger assembly configured to accept various retractable needle assemblies, which are capable of cooperating to provide a retraction safety syringe. In particular, the syringe includes a barrel and a retraction plunger assembly comprising a control unit attached to a plunger and releasably engaged to a housing, and at least one biasing means disposed within the plunger assembly. Upon completion of dose delivery via a retractable needle, the control unit disengages from housing and the biasing member retracts the plunger and a connected needle into the barrel. Various elements are configured to prevent further use of the syringe. The control unit can be used to control a rate of needle retraction.

One embodiment is directed to a system for injecting, comprising a syringe body defining an interior medicine chamber; a stopper member configured to be inserted into the interior medicine chamber to contain medicine within the medicine chamber; a plunger member configured to be manually manipulated to insert the stopper member relative to the syringe body; and a needle having proximal and distal ends, the proximal end comprising an anchoring geometry configured to be at least partially inserted into the stopper member such that upon retraction of the stopper member, the needle is pulled proximally along with the stopper to be at least partially contained within the interior medicine chamber.