Hverken lamivudin eller zidovudin er mutagent i bakterieforsøg, men viser som mange andre nukleosidanaloger aktivitet i in- vitro pattedyrsforsøg, såsom muselymfomcelletesten.
Neither lamivudine nor zidovudine are mutagenic in bacterial tests, but like many nucleoside analogues they show activity in in vitro mammalian tests such as the mouse lymphoma assay.