Wearable automatic injection device for controlled delivery of therapeutic agents

摘要

Exemplary embodiments provide wearable automatic injection devices for subcutaneously injecting a therapeutic agent into a patient's body at controlled rates, for example, in a single bolus. Exemplary embodiments provide methods for assembling wearable automatic injection devices for subcutaneously injecting a therapeutic agent into a patient's body at controlled rates. Exemplary embodiments provide methods for using wearable automatic injection devices for subcutaneously injecting a therapeutic agent into a patient's body at controlled rates.

主权项

1. A wearable automatic injection device free of a battery for providing a subcutaneous injection of a therapeutic agent into a patient, the wearable automatic injection device comprising:
a housing comprising a patient contact portion securable to the patient; an injection assembly moveably disposed in the housing holding a hypodermic injection needle for insertion into the patient, the injection assembly moveable between a retracted position in which the injection needle does not protrude outside the housing and an extended position in which the injection needle protrudes outside the housing; a vessel provided in the housing for holding the therapeutic agent; a plunger moveably disposed in the vessel for ejecting the therapeutic agent from the vessel into the injection assembly; a plunger actuation mechanism for actuating the plunger using a mechanical or hydraulic mechanism within the vessel; a retraction trigger responsive to a change of state of the wearable automatic injection device from an injection state to a post-injection state, wherein the wearable automatic injection device enters the post-injection state upon completion of delivery of a therapeutically effective dose of the therapeutic agent and enters the post-injection state upon removal of the wearable automatic injection device from the patient prior to completion of delivery of the therapeutically effective dose of the therapeutic agent; and a retraction mechanism for automatically retracting the injection assembly from the extended position in the injection state to the retracted position in the post-injection state upon triggering by the retraction trigger.