Venetoclax showed significant preclinical activity in BCL-2 driven haematological malignancies in vivo and due to its highly promising results in early phase clinical trials in patients with relapsed or refractory chronic lymphocytic leukaemia, was fast-tracked for approval in the USA, and subsequently approved in other countries for use in a variety of blood cancers, either as a single agent, or combined with other targeted therapies such as Rituximab, where results have been particularly impressive [238]. The gene discussed is BCL2; the disease is B-cell chronic lymphocytic leukemia.