In the large pivotal phase II study, BIRCH, the investigational cancer immunotherapy Atezolizumab ( MPDL3280A; anti-PD-L1 ) met its primary endpoint and shrank tumors ( objective response rate; ORR ) in people with locally advanced or metastatic non-small cell lung cancer ( NSCLC ) whose disease expressed PD-L1 ( Programmed Death Ligand-1 ).
The study showed the amount of PD-L1 expressed by a person's cancer correlated with their response to the medicine.
Adverse events were consistent with what has been previously observed for Atezolizumab.
In 2015, the FDA ( Food and Drug Administration ) granted Atezolizumab a Breakthrough Therapy Designation for the treatment of people whose NSCLC expresses PD-L1 and who progressed during or after standard treatments ( e.g., Platinum-based chemotherapy and appropriate targeted therapy for EGFR mutation-positive or ALK-positive disease ).
This designation is designed to expedite the development and review of medicines intended to treat serious diseases.
Seven phase III studies are evaluating Atezolizumab alone or in combination with other medicines as a potential new treatment for people with early and advanced stages of lung cancer.
BIRCH is an open-label, multicenter, single-arm phase II study that evaluated the safety and efficacy of Atezolizumab in 667 people with locally advanced or metastatic NSCLC whose disease expressed PD-L1.
PD-L1 expression was assessed on both tumor cells ( TC ) and tumor-infiltrating immune cells ( IC ) with an investigational immunohistochemistry test ( IHC ) being developed by Roche Diagnostics.
Eligibility criteria included people whose tumors were determined to express PD-L1 with an IHC score of TC2/3 or IC2/3. People in the study received a 1200-milligram intravenous dose of Atezolizumab every three weeks.
The primary endpoint of the study was ORR. Secondary endpoints included duration of response ( DoR ), overall survival ( OS ), progression-free survival ( PFS ) and safety.
Atezolizumab is an investigational monoclonal antibody designed to interfere with a protein called PD-L1. Atezolizumab is designed to target PD-L1 expressed on tumor cells and tumor-infiltrating immune cells, preventing it from binding to PD-1 and B7.1 on the surface of T cells. By inhibiting PD-L1, Atezolizumab may enable the activation of T cells.
According to the American Cancer Society ( ACS ), it is estimated that more than 221,000 Americans will be diagnosed with lung cancer in 2015, and NSCLC accounts for 85% of all lung cancers. It is estimated that approximately 60% of lung cancer diagnoses in the United States are made when the disease is in the advanced stages. ( Xagena )
Source: Genentech, 2015