Injection devices for delivering pharmaceutical compositions into the eye are described. Some devices include a resistance component for controllably deploying an injection needle through the eye wall. The resistance component may be disposed on the injector device, or on a portion of the injection device housing, or on a drug reservoir. Some devices may be removably attached to a drug reservoir, for example, through a luer connector. Other devices may comprise internal luer seal for securely connecting a drug conduit of the device to the luer cavity of a drug reservoir. Yet other devices may comprise a priming-enabling element to facilitate the drug priming of a shielded needle. Related methods and systems comprising the devices are also described.