New research presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting indicates that nivolumab neoadjuvant therapy is safe and provides anti-tumor activity in inflammatory breast cancer, a rare but aggressive form of the disease.
“Inflammatory breast cancer is the most aggressive form of breast cancer, with poor prognosis, and is often resistant to neoadjuvant systemic therapy, with early recurrence and metastases,” wrote the authors, led by Maryann J. Kwa, of the NYU Perlmutter Cancer Center, NYU Langone Health, in New York, New York. “PD-L1 expression … is moderate to high, and blockade of the PD-1/PD-L1 axis with checkpoint inhibitors has emerged as a promising treatment to enhance clinical response.”
The researchers explored the efficacy of neoadjuvant nivolumab (an anti-PD-1 antibody) combined with chemotherapy in this disease state. The multicenter pilot study enrolled 8 women with a mean age of 57 years who had newly diagnosed non-metastatic inflammatory breast cancer of any subtype (estrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2).
The patients received nivolumab 360 mg on day 1 of a 21-day cycle for 4 cycles, along with standard chemotherapy, depending on subtype. Each patient also had a modified radical mastectomy, followed by radiation and adjuvant therapy. The researchers collected breast tissue for biopsy, residual tumor tissue, and peripheral blood samples for biomarker testing.
All 8 patients completed therapy, and none experienced grade 4 toxicity. Three women had grade 3 neutropenia, 2 had immune-related diarrhea/colitis, and 1 had elevated levels of liver transaminases.
No patients experienced disease progression. At the time of surgery, 4 patients had reached pathologic complete response. Using the Residual Cancer Burden (RCB) tool, the researchers placed 1 patient at RCB-I, 2 at RCB-II, and 1 at RCB-III. At the time of the presentation, those patients remained free of evidence of disease.
The authors concluded that adding nivolumab to neoadjuvant therapy was safe and tolerable, providing anti-tumor activity in inflammatory breast cancer. They recommended further research into checkpoint inhibitors for treatment of the disease.