In Vitro: WEHI-539 is a selective inhibitor of Bcl-XL. WEHI-539 augments Carboplatin induced caspase 3/7 activity, PARP cleavage and annexin V labelling. WEHI-539 as a single agent causes noticeable PARP cleavage in Ovcar-4 (5 μM in Ovcar-4.) and Ovsaho (1 μM in Ovsaho) cells.