The abstract of the underlying research paper: https://www.mdpi.com/1999-4923/14/11/2290/htm contains the quote "Vaccination prevented decreases on physiological measures (oxygen saturation, heart rate) and reduction in overall activity following FEN administration in male rats." These physiological measures are the precursors to overdose, which occurs when low oxygen saturation becomes hypoxia and becomes fatal.

To summarize, yes, this vaccine prevents overdose, as well as the other drug effects.