Sacituzumab Govitecan (drug) as a new first-line therapy compared to standard therapy for triple-negative, advanced, inoperable breast cancer

Breast cancer (mammary carcinoma) is a malignant disease of the mammary gland tissue characterized by the uncontrolled proliferation of mammary gland cells. Treatment of the disease depends on numerous factors, such as the patient’s overall health, the tumor’s growth rate (Ki-67 index), the presence of detectable hormone receptors on the surface of the cancer cells, and the increased expression of the HER2 receptor on the cells (HER2-positive). If none of these receptors are present, the cancer is referred to as triple-negative breast cancer. The stage of the disease is also very important. While in the locally confined stage (Stages 1–2A) the disease is limited to the breast and a cure is highly likely, the locally advanced stage (Stages 2B–3) means that the tumor is already larger or that lymph nodes are involved. In Stage 4, metastases are present, meaning the tumor has spread throughout the body, and a cure is highly unlikely at this stage. The goal then is to use various therapies to “keep the disease in check” for as long as possible. Triple-negative breast cancer is generally more difficult to treat than other forms, as fewer treatment options are available. To date, the standard of care for untreated triple-negative breast cancer with detectable distant metastases has been chemotherapy. Sacituzumab govitecan-hziy is a novel drug, an antibody-drug conjugate, which specifically binds to cancer cells and directly releases the cancer-killing agent there. The drug is already approved for the treatment of triple-negative metastatic breast cancer and other subtypes when other standard therapies are no longer effective.

The goal of this Phase 3 study is to investigate the efficacy and safety of treatment with sacituzumab govitecan-hziy in a larger number of patients who have triple-negative, advanced/metastatic breast cancer and have not yet received any treatment, or whose last chemotherapy was more than 6 months ago. Patients will be randomly assigned to one of two study arms. Group 1 will receive sacituzumab govitecan-hziy as an infusion via a venous access on Days 1 and 8 of a 21-day cycle. Group 2 will receive standard chemotherapy (the exact regimen will be selected by the treating physicians) with paclitaxel, nab-paclitaxel, or gemcitabine + carboplatin. The study is open-label, meaning that both the medical staff and the study participants know which medications are being administered. Treatments and follow-up examinations as part of the study will continue for up to 5 years, during which the effectiveness of the therapy and the occurrence of side effects from the various medications will be evaluated. The key factor is whether or when the disease progresses again during treatment.

Women and men aged 18 and older with triple-negative, locally advanced, inoperable, or metastatic breast cancer are eligible to participate in this study. The disease must either be untreated, or the last course of chemotherapy must have taken place more than 6 months ago. If the tumor expresses the PD-L1 receptor on its surface, the patient must have already received therapy targeting PD-L1 or must be ineligible for such therapy due to pre-existing conditions.