Atezolizumab, paclitaxel and bevacizumab as first line therapy in triple-negative breast cancer

In the ATRACTIB trial, recently published on Nature Medicine,  the combination of atezolizumab, paclitaxel and bevacizumab as first-line treatment for patients with advanced triple-negative breast cancer (aTNBC) showed a promising progression-free survival with no new safety signals.

The current first-line treatment for aTNBC is determined by the expression of PD-L1 but despite treatment advancements, the median overall survival for aTNBC remains poor. As authors say, «There is also a critical need to explore the potential synergism of the immunotherapies in combination with other targeted or cytotoxic agents». Thus the ATRACTIB trial evaluated a combination of atezolizumab, paclitaxel and bevacizumab as first-line treatment in 100 patients with aTNBC. The median progression-free survival was 11 months and objective response rate was 63%, with 14% of patients who had complete responses and 49% who had partial responses;  the median overall survival was 27.4 months. All patients experienced treatment emergent adverse events, with 61% presenting grade 3 or 4 adverse events; no treatment-related deaths or new safety signals were observed. As authors conclude, «The ATRACTIB study demonstrated that the combination of atezolizumab plus paclitaxel and bevacizumab exhibits encouraging antitumor activity as a first-line treatment for patients with aTNBC, irrespective of PD-L1 expression.  Importantly, bevacizumab appears to improve the efficacy of immunotherapy in this patient population. Our findings warrant further investigation by evaluating the role of bevacizumab in combination with emerging antibody-drug conjugates and immunotherapies, regardless of PD-L1 status».