Breast Cancer Drug Combined with Immunotherapy Improves Survival

Celgene Corporation recently announced positive results from the phase 2 tnAcity trial at the 2016 San Antonio Breast Cancer Symposium. The trial evaluated the safety and efficacy of Abraxane for injectable suspension (paclitaxel protein-bound particles for injectable suspension) (albumin-bound) in patients with breast cancer.

Investigators found that a weekly combination of Abraxane plus carboplatin resulted in longer progression-free survival (7.4 months) compared with weekly regimens of Abraxane plus gemcitabine (5.4 months), or carboplatin plus gemcitabine (6 months), as the first-line treatment, according to a press release from Celgene.

Included in the trial were 191 patients with metastatic triple-negative breast cancer randomized to receive 1 of the 3 aforementioned treatment regimens. In addition to longer progression-free survival (PFS), researchers also found that patients treated with Abraxane plus carboplatin had a longer median treatment duration compared with patients taking the other drug regimens.

The primary endpoint researchers evaluated was PFS, and secondary endpoints included overall survival and objective response rate.

In all treatment arms, common adverse events included neutropenia, anemia, thrombocytopenia, leukopenia, febrile neutropenia, peripheral neuropathy, and fatigue. Approximately 45% of patients in the Abraxane treatment arm discontinued the study due to adverse events, compared with 25% of patients in each of the other treatment arms.

Common adverse events that lead to discontinuation of the drug included thrombocytopenia, anemia, neutropenia, and drug hypersensitivity.

Abraxane is indicated in patients with breast cancer who have failed a combination treatment for metastatic disease, or who relapsed within 6 months of adjuvant chemotherapy, such as anthracycline, according to the press release.

"Metastatic triple negative breast cancer is one of the most challenging types of cancers for treating physicians and patients alike, and there remains an important unmet need in these patients to find more effective treatment options," said Denise A. Yardley, MD, senior investigator at Breast Cancer Research Program; principal investigator at Sarah Canon Research Institute. "These data add to the body of knowledge about Abraxane in metastatic triple negative breast cancer, a disease that requires additional research."

Despite these positive findings, Celgene has decided against moving forward with phase 3 clinical trials due to the changing landscape of breast cancer treatment. Instead, Celgene will focus on researching Abraxane plus immunotherapy combination treatments in patients with breast cancer.

Celgene remains committed to applying these positive findings to patients with metastatic breast cancer whose needs are typically not met, according to the press release.

"The findings of tnAcity are encouraging, illustrating that an Abraxane-containing regimen may have activity in a type of breast cancer with few viable treatments and these findings give researchers additional insight into how to treat metastatic triple negative breast cancer," said Michael Pehl, president, Hematology and Oncology for Celgene. "Celgene is committed to continuing to support research in breast cancer to identify regimens for patients with aggressive disease and in areas with limited treatment options."