Abstract: An in vitro toxicity assay comprising: a) exposing a spheroid sample to a selected concentration of a compound to be assayed; b) incubating the spheroid sample for a suitable period of time; and c) observing if spheroid cell spreading inhibition takes place.

Abstract: There is disclosed a method for the formation of spheroids comprising: (a) obtaining and/or deriving a plurality of cells from a tissue or an organ or from a part thereof; (b) orbitaly rotating the cells in a fluid medium at a first speed and for a time sufficient for spheroids to form; and (c) further orbitally rotating the spheroids formed in step (b) in a fluid medium at a second speed or speeds, slower than said first speed.