Assessment of elimination half life of mAb

Dear all I need some help to assess the elimination half life of a monoclonal antibody. The model that describes the data is a QSS aproximation of TMDD with Rmax constant. The model includes two binding process of mAb to its target: in central and peripheral compartments. Is there any specific equation to calcule lambda z and the elimination half life for each of the TMDD aproximations? Thanks Niurys