The Food and Drug Administration has granted accelerated approval for the combination of atezolizumab (Tecentriq) plus nanoparticle albumin–bound paclitaxel (nab-paclitaxel; Abraxane) for the treatment of adults with unresectable locally advanced or metastatic programmed death-ligand 1 (PD-L1)–positive triple-negative breast cancer (TNBC).
This conditional approval is granted to medicines that fill an unmet medical need for serious or life-threatening diseases or conditions, but the FDA may require confirmatory trials to provide verification and description of clinical benefit to allow continued approval.
The approval is based on the phase 3 IMpassion130 trial (), which enrolled 902 patients with unresectable, locally advanced or metastatic TNBC who had not received prior lines of chemo for metastatic disease, according to .
The multicenter, randomized, double-blind study has been evaluating the drug combination’s efficacy, safety, and pharmacokinetics. Compared with placebo plus nab-paclitaxel, atezolizumab/nab-paclitaxel demonstrated significantly superior progression-free survival (median PFS, 7.4 months vs. 4.8 months; hazard ratio, 0.60; 95% confidence interval, 0.48-0.77; P less than .0001).
The overall survival data for the intention-to-treat population remains immature, but further data will be shared with the FDA in the future, according to Genentech.
No new safety signals were seen in the atezolizumab/nab-paclitaxel arm, and the combination’s safety appeared consistent with the known safety profiles of each medicine individually.
The most common grade 3-4 events (occurring in more than 2% of patients) in the combination arm included low red blood cells, low white blood cells, feeling tired, low blood potassium level, and pneumonia.
The most common side effects (occurring in more than 20% of patients) in the combination arm included hair loss, tingling, nausea, diarrhea, headache, low red blood cells, low white blood cells, and decreased appetite.
Atezolizumab is a monoclonal antibody that binds to the PD-L1 receptor, which could possibly lead to the reactivation of T cells; however, atezolizumab also may interact with other cells in the body. Nab-paclitaxel is an injectable suspension of the common chemotherapy drug.