Embodiments of the present disclosure are directed to systems and methods for device exchange in an endoscopic procedure. In one implementation, a system for device exchange in an endoscopic procedure includes an elongated device having a slit extending from a distal end to a proximal end of the elongated device, a main block, and an adapter. The main block is configured to be affixed to a port of an endoscope. The main block includes a main channel for receiving a guidewire and the elongated device. The adapter can be engaged with the main block and configured to merge the guidewire into the elongated device. The adapter includes a working channel for receiving the elongated device and a working member raising from an inner wail of the working channel. When the elongated device passes through the working channel, the working member wedges open a portion of the slit of the elongated device such that a portion of the guidewire merges into the elongated device through the opened portion of the slit.