Injection system

An injection system, comprising:

• a container configured to contain a pharmaceutical product, the container having a proximal end, a distal end, and an inner surface extending between the proximal end and the distal end;
• a plunger positioned within the container and having a surface that slidably engages the inner surface of the container;
• a plunger rod connected to the plunger, the plunger rod extending from the plunger such that at least a portion of the plunger rod is positioned externally to the proximal end of the container;
• a housing at least partially surrounding the container;
• and
• a plunger rod cover removably coupled to the housing and enclosing the portion of the plunger rod positioned externally to the container, the plunger rod cover being configured to be removed from the housing to allow access to the plunger rod, wherein removal of the plunger rod cover moves the container from an inactivated position to an activated position;
• wherein the housing includes a pawl that is configured to engage a cam surface on the plunger rod cover such that rotation of the plunger rod cover relative to the housing causes the plunger rod cover to be moved away from the housing.

An injection system comprising:

• a container having a proximal end, a distal end, and an interior surface, the interior surface defining a cavity for containing a pharmaceutical product;
• a plunger disposed in the cavity defined by the container, the plunger having a surface constructed to sealingly engage the interior surface of the container whereby a seal is maintained between the plunger and the interior surface of the container as the plunger is moved within the cavity;
• a plunger rod attached to the plunger, the plunger rod extending proximally from the plunger such that a portion of the plunger rod is disposed externally to the container;
• a housing at least partially surrounding the container;
• a plunger rod cover defining an interior space, the plunger rod cover being removably attached to the housing;
• and
• a driver mounted on the housing, the driver being configured to engage the plunger rod cover when the injection system is in a first, inactivated state, the driver further being configured to move the injection system from the first, inactivated state to a second, activated state upon removal of the plunger rod cover from the housing;
• wherein the plunger rod cover is constructed to be removed by rotating the plunger rod cover relative to the injection system.

A method for delivering a pharmaceutical product comprising:

• providing an injection system comprising:
• a container containing the pharmaceutical product, the container having a proximal end, a distal end, and an inner surface extending between the proximal end and the distal end, the inner surface of the container defining an interior volume for containing the pharmaceutical product;
• a plunger positioned within the container and having a surface that slidably engages the inner surface of the container;
• a plunger rod connected to the plunger, the plunger rod extending from the plunger such that at least a portion of the plunger rod is positioned externally to the proximal end of the container;
• a plunger rod cover removably coupled to a housing at least partially surrounding the container, the plunger rod cover enclosing the portion of the plunger rod positioned externally to the container, the plunger rod cover being configured to be removed from the housing to allow access to the plunger rod;
• and
• a driver constructed to transduce rotation of the plunger rod cover to transition the injection system from an inactivated state in which the pharmaceutical product in the container cannot be delivered therefrom to an activated state in which the pharmaceutical product in the container can be delivered from the container;
• rotating the plunger rod cover and removing the plunger rod cover from the housing, thereby transitioning the injection system from the inactivated state to the activated state;
• and
• applying a distally directed force to the plunger rod in order to deliver the pharmaceutical product from the container.