An insertion mechanism (200, 2200) and methods of assembly and operation of a drag pump (1) may include an insertion mechanism housing (202, 2202)； a housing cap (203)； a manifold guide (220, 2220)； an insertion biasing member (210, 2210) initially held in an energized state； a retraction biasing member (216, 2216) connected to a hub (212, 2212) connected to a proximal end of a needle (214, 2214)； and optionally, a clip retainer (219, 2219). The retraction biasing member is held initially in an energized state between the hub and manifold guide. A manifold has a manifold body (240B, 2240B) and one or more septa (230A, 230B, 2230A, 2230B) defining a manifold header (242, 2242). The retraction biasing member may be held initially in an energized state between the hub and the clip retainer. The needle is advanced by the insertion biasing member(s) from the initial configuration to an administration configuration, opening a fluid pathway from the manifold header to the target. The drug delivery pump may include an activation mechanism (14), a dreive mechanism (100), a fluid pathway connection (300), and the insertion mechanism (200).
