Venetoclax: A Review in Previously Untreated Chronic Lymphocytic Leukaemia

Venetoclax (Venclexta®; Venclyxto®) is a first-in-class, oral, selective inhibitor of B cell lymphoma 2 (BCL2). In several countries, including the USA and those of the EU, venetoclax is indicated in combination with obinutuzumab for the treatment of adult patients with previously untreated chronic lymphocytic leukaemia (CLL). Approval was based on the results of the phase III CLL14 trial in patients with previously untreated CLL and co-existing conditions. In this study, fixed-duration (12 months) targeted treatment with venetoclax + obinutuzumab resulted in significantly longer progression-free survival (PFS; primary endpoint) relative to fixed-duration chemoimmunotherapy with chlorambucil + obinutuzumab. Venetoclax + obinutuzumab was also associated with significantly higher rates of undetectable minimal residual disease (MRD), complete response and overall response than chlorambucil + obinutuzumab. Improvements in clinical outcomes with venetoclax + obinutuzumab were maintained during long-term follow-up, when all patients had been off treatment for ≥ 2 years. No significant between-group difference was observed in overall survival (OS). Venetoclax had an acceptable tolerability profile. Notable adverse events such as grade 3 or 4 neutropenia can be managed with supportive therapy and venetoclax dose modifications. In conclusion, fixed-duration venetoclax + obinutuzumab represents an important chemotherapy-free first-line treatment option for patients with CLL, particularly those who are not fit enough to receive intensive chemoimmunotherapy.