FDA: Efficacy, Safety Concerns With Breast Cancer Combo Therapy

The Food and Drug Administration (FDA) is alerting health care professionals that paclitaxel protein-bound (Abraxane) should not be replaced with paclitaxel in clinical practice based on findings from a phase 3 study investigating the combination of atezolizumab with paclitaxel in patients with previously untreated inoperable locally advanced or metastatic triple-negative breast cancer (TNBC).

The multicenter, double-blind, placebo-controlled phase 3 IMpassion131 study assessed the efficacy and safety of atezolizumab, a PD-L1 blocking antibody, plus paclitaxel in 651 adult patients with previously untreated, inoperable locally advanced or metastatic, centrally confirmed TNBC. Findings showed that the combination did not meet statistical significance for progression free survival and also demonstrated a negative trend in overall survival (secondary end point) compared with the paclitaxel + placebo arm.

According to the Agency, data from the study will be reviewed and new information related to any potential prescribing changes will be communicated based on the results. Ongoing trials investigating this combination for breast cancer will also be evaluated.

While atezolizumab in combination with paclitaxel is not approved for breast cancer, atezolizumab (Tecentriq; Genentech) in combination with paclitaxel protein-bound (Abraxane; Celgene) has been approved through an accelerated pathway for the treatment of unresectable locally advanced or metastatic TNBC in patients whose tumors express PD-L1. Continued approval for this indication is contingent upon verification and description of clinical benefit in confirmatory trials.

For more information visit fda.gov.

Reference

FDA alerts health care professionals and oncology clinical investigators about efficacy and potential safety concerns with atezolizumab in combination with paclitaxel for treatment of breast cancer. https://www.fda.gov/drugs/drug-safety-and-availability/fda-alerts-health-care-professionals-and-oncology-clinical-investigators-about-efficacy-and. Accessed September 9, 2020.