The present invention concerns an intervertebral prosthesis device and a fixation device for fixing an intervertebral prosthesis device to an adjacent vertebra (V), characterized in that the fixation device comprises at least one anchoring tongue (51, 52) configured to be impacted into a plate (V0) of a vertebra (V), through at least a portion of said intervertebral prosthesis device and a stop (53) configured to abut on said intervertebral prosthesis device and retain the fixation device to said intervertebral prosthesis device.