The FDA has issued an alert to health care providers and clinical investigators regarding the safety and efficacy of atezolizumab in combination with paclitaxel. According to the alert, the treatment combination fails to improve outcomes for patients with previously untreated inoperable locally advanced or metastatic triple negative breast cancer.
The Agency released the alert to ensure that atezolizumab in combination with paclitaxel is not used in clinical practice. The combo recently completed and failed a phase 3 clinical trial compared to placebo. However, the FDA noted that a different combination therapy, atezolizumab in combination paclitaxel protein-bound, is approved for use in this patient population.
“Health care professionals should not replace paclitaxel protein-bound with paclitaxel in clinical practice,” the FDA wrote.
A recent phase 3 clinical trial, IMpassion131, showed that atezolizumab and paclitaxel failed to significantly reduce progression risk or mortality compared to a placebo/paclitaxel combination in PD-L1 positive patients. Additionally, data showed that the placebo/paclitaxel combination group demonstrated higher overall survival compared to the atezolizumab/paclitaxel group, across all mTNBC patients.
Atezolizumab and paclitaxel is not currently FDA approved for the treatment of breast cancer. The FDA noted that patients taking atezolizumab and paclitaxel for an FDA approved indication should continue to take the treatment.
Additionally, the FDA explained that “continued approval of atezolizumab in combination with paclitaxel protein-bound,” in breast cancer patients “may be contingent on proven benefit of the treatment in additional trials.” The combination is currently approved for mTNBC patients with PD-L1 positive tumors.