Breastlink has partnered with researchers to explore an investigational cancer immunotherapy called atezolizumab (MPDL3280A) in the treatment of metastatic triple-negative breast cancer. In early-stage trials, atezolizmab was effective in patients previously treated for triple-negative breast cancer. A new trial will investigate atezolizumab with chemotherapy in metastatic triple-negative breast cancer patients who have not received prior systemic therapy for incurable disease.

Atezolizumab Triple-Negative Breast Cancer Treatment

What is Atezolizumab?

Atezolizumab is a type of immunotherapy that may restore the body’s immune system to fight cancer. atezolizumab works by blocking a type of protein called PD-L1. This protein can protect cancer cells from destruction by the immune system. By inhibiting PD-L1, atezolizumab may enable the activation of T cells, allowing these immune cells to effectively detect and attack tumor cells.

In an early stage trial, researchers administered atezolizumab to patients with metastatic triple-negative breast cancer who had previously received systemic therapy. Among 21 patients evaluable for efficacy, tumor shrinkage was seen in four of these patients and disease control appeared to be ongoing in three patients at the time of the report.

Atezolizmab has also been effective in the treatment of other cancers. The FDA has granted atezolizumab Breakthrough Therapy Designation as a treatment in metastatic lung and bladder cancer patients whose tumors express the PD-L1 protein. This designation is reserved for therapies that appear significantly more effective, based on clinical evidence, than currently approved therapies.

Ongoing Atezolizmab Research

Triple-negative breast cancer, which accounts for around 15 percent of all breast cancer cases, is generally associated with a poorer prognosis than other breast cancer sub-types. Early results show strong potential for atezolizmab as a treatment for triple-negative breast cancer, as well as for immune checkpoint inhibitor strategies in general.

In a phase III trial sponsored by drugmaker Hoffman-La Roche, researchers are investigating the use of atezolizumab in combination with nab-paclitaxel, a type of chemotherapy, in patients with metastatic breast cancer. The phase III trial is currently recruiting patients. Eligible candidates include women with metastatic or inoperable locally advanced triple-negative breast cancer with no prior chemotherapy or targeted systemic therapy for inoperable disease.

To learn more about the phase III trial investigating atezolizumab in previously untreated patients with metastatic triple-negative breast cancer, visit clinicaltrials.gov.