This paper presents the design of a driver steering assistance system, which provides a corrective torque in order to guide the driver. While designing such a system, it is important to consider the interactions since the driver modifies the transfer function from the control input to the output of interest during a shared steering task. The novelty of our approach lies in the formulation of the predictive controller, which employs amodel of the driver-in-the-loop steering dynamics, where an online parameter identification scheme is proposed to track the time-varying parameters of the process. An optimal guidance torque is calculated with respect to the level of interaction using the updated model. We validate the proposed approach by performing an experimental study with five participants in a guided lane, keeping task under different interaction behaviors of participants. The results show the system capability to adapt the control input based on the driver's acceptance on the torque intervention.