Drug delivery with an improved piston rod

摘要

An improved drug delivery device is provided having a piston rod that incorporates on its proximal end at least one guidepost that is configured for transmitting axial and rotational forces from a drive mechanism. The device comprises a drug delivery device housing and a medicament contained in the drug delivery device housing.

主权项

1. A piston rod for a device, especially a pen-type injector, comprising an elongated member having a distal end and a proximal end where the proximal end has at least two sets of guideposts, where at least one set has at least two guideposts that are in axial alignment with each other and are configured for transmitting axial and rotational forces from a drive member having at least one internal groove with a pitch P, wherein each guidepost is configured as a post, peg, or pin having a single longitudinal axis projecting radially outward from the proximal end and the at least two sets of guideposts are located on opposing sides of the proximal end of the piston rod.