Phase 3 IMpassion031 Study of Atezolizumab in Combination with Chemo Meets Primary Endpoint

Updated data from the phase 3 IMpassion031 study, evaluating atezolizumab (Tecentriq) in combination with chemotherapy (albumin-bound paclitaxel and nab-paclitaxel [Abraxane], followed by doxorubicin and cyclophosphamide) versus placebo plus chemotherapy, met its primary end point, according to Genentech, the developer of atezolizumab.

The combination of atezolizumab and chemotherapy demonstrated a statistically significant and clinically meaningful improvement in pathological complete response (pCR) for the treatment of individuals with early triple-negative breast cancer (TNBC), regardless of PD-L1 expression. 

Results from the study will be presented at an upcoming medical meeting and will be discussed with global health authorities.

“Triple-negative breast cancer remains an aggressive disease with high rates of recurrence,” Levi Garraway, MD, PhD, chief medical officer and head of Global Product Development at Genentech, said in a press release. “Our goal in treating TNBC at its earliest stages is to provide people with the best chance for a future cure. Adding [atezolizumab] to chemotherapy now has the potential to help women with TNBC at multiple different stages of the disease.”

In the multicenter, randomized, double-blind, phase 3 IMpassion031 study, fewer patients who were given the atezolizumab combination as a neoadjuvant treatment had evidence of tumor tissue detectable at the time of surgery compared to the control arm.

Secondary end points for the study include overall survival (OS), event-free survival, disease-free survival, and quality of life (QOL) measures.

Importantly, safety for the atezolizumab combination appeared to be consistent with the known safety profiles of the individual medicines and no new safety signals were reported.

This study is the second positive phase 3 study from Genentech showing the benefit of atezolizumab in TNBC, as well as the first study of atezolizumab to demonstrate benefit in early TNBC. Currently, atezolizumab in combination with nab-paclitaxel is approved in more than 70 countries worldwide, including the US and across Europe, for the treatment of adults with unresectable locally advanced or metastatic TNBC in people whose tumors express PD-L1 (IC≥1%).

Breast cancer is the most prevalent cancer among women worldwide. According to the American Cancer Society, approximately 280,000 people in the US will be diagnosed with invasive breast cancer, and more than 42,000 will die from the disease in 2020. In addition, based on the results of diagnostic tests, about 15% of breast cancers are triple-negative.

Notably, Genentech indicated that they have an extensive development program for atezolizumab, including multiple ongoing and planned phase 3 studies across lung, genitourinary, skin, breast, gastrointestinal, gynecological, and head and neck cancers. This includes studies evaluating atezolizumab both alone and in combination with other medicines.

Reference:

Genentech’s Tecentriq in Combination With Chemotherapy (Including Abraxane) Meets Primary Endpoint of Improved Pathological Complete Response, Regardless of PD-L1 Status, as Initial Treatment for People With Early Triple-negative Breast Cancer [news release]. South San Francisco, CA. Published June 17, 2020. gene.com/media/press-releases/14860/2020-06-17/genentechs-tecentriq-in-combination-with. Accessed June 18, 2020.