- The FDA has granted accelerated approval for atezolizumab in combination with nab-paclitaxel for the treatment of PD-L1+ unresectable locally advanced or metastatic triple-negative breast cancer (TNBC).
- The VENTANA PD-L1 assay was also approved as a companion diagnostic device.
Why this matters
- The immune checkpoint inhibitor was previously indicated for urothelial carcinoma and nonsmall cell lung cancer.
- Full prescribing information can be found here.
- The FDA's approval was predicated on a single trial: the IMpassion130 multicenter international double-blind, placebo-controlled trial. It consisted of 902 patients with unresectable locally advanced or metastatic TNBC given atezolizumab or placebo in combination with nab-paclitaxel.
- Best response was observed in patients with PD-L1+ expressing tumors (median PFS, 7.4 vs 4.8 months; HR, 0.60; P<.0001>
- The FDA-recommended dose is 840 mg administered intravenously over the course of 60 minutes, followed by 100 mg/m2 nab-paclitaxel.
- Atezolizumab is recommended on days 1 and 15 of a 28-day cycle, with nab-paclitaxel on days 1, 8, and 15.
- The most frequent adverse reactions (incidence ≥20%) with atezolizumab alone were fatigue, nausea, constipation, cough, dyspnea, and decreased appetite.