- Immunotherapy durvalumab+olaparib followed by chemotherapy shows superior pathologic complete response (pCR) rate in patients with HER2-negative (HER2-) breast cancer, including those with estrogen receptor-positive (HR+) tumors and triple-negative breast cancer (TNBC).
Why this matters
- Lead author said, “results provide further evidence for the clinical value of immunotherapy in early-stage breast cancer.”
- Results from one arm of the ongoing phase 2, Investigation of Serial Studies to Predict Your Therapeutic Response Through Imaging and Molecular Analysis 2 (I-SPY 2) trial.
- 73 women with high-risk, HER2- breast cancer received durvalumab+olaparib with paclitaxel followed by doxorubicin+cyclophosphamide.
- 299 patients in the control group received paclitaxel followed by doxorubicin+cyclophosphamide.
- Funding: William K. Bowes Jr Foundation; others.
- 21 patients with TNBC and 52 patients with HR+ tumors received durvalumab and olaparib.
- Durvalumab and olaparib increased pCR rates compared with control patients in:
- HER2- group: 37% vs 20%
- TNBC group: 47% vs 27%
- HR+/HER2- group: 28% vs 14%
- No new safety signals were reported.
- Immune-related grade 3 adverse event rate was 19% in the durvalumab, olaparib group vs 1.6% in the control group.
Pamela N. Munster, MD, from the University of California, San Francisco commented, “the signal of a better pCR rate among patients in the ultra-high Mammaprint group may allow selection of patients with HR-positive disease who may benefit from immunotherapeutic agents and/or PARP inhibitors.”