Trodelvy: A New Option for Triple-Negative Breast Cancer

Trodelvy: A New Option for Triple-Negative Breast Cancer

Breast cancer is the most common cancer among women worldwide, and about 15% of cases are triple-negative, meaning that the cancer cells do not have receptors (targets) for estrogen, progesterone, or HER2 (a protein that stimulates cell growth and survival). Triple-negative breast cancer is an aggressive type of breast cancer that tends to grow and spread faster than other types. It is also more likely to recur after treatment and has fewer treatment options.

Fortunately, there is a new drug that targets triple-negative breast cancer and improves the outcomes of patients with this disease. This drug is called Trodelvy, and it belongs to a class of drugs called antibody-drug conjugates. Trodelvy works by delivering a powerful chemotherapy agent directly to the cancer cells, while sparing the normal cells.

Trodelvy contains two active components: a monoclonal antibody (a type of protein) that has been designed to recognise and attach to Trop-2, a protein found on many breast cancer cells, and a small molecule called SN-38, which is a potent inhibitor of an enzyme called topoisomerase I, which is involved in copying cell DNA needed to make new cells. By blocking the enzyme, Trodelvy prevents the cancer cells from multiplying and eventually causes them to die.

Trodelvy has been tested in clinical trials involving patients with unresectable (cannot be removed by surgery) or metastatic (spread to other parts of the body) triple-negative breast cancer who have received two or more prior systemic (whole body) treatments, at least one of them for advanced disease. The results of these trials have been promising.

In the ASCENT trial1, Trodelvy significantly improved overall survival (the time from randomization to death from any cause) and progression-free survival (the time without disease worsening) compared to standard treatment (chemotherapy) in patients with metastatic triple-negative breast cancer. The median overall survival was 12.1 months in the Trodelvy group versus 6.7 months in the standard treatment group, which translates to a 49% reduction in the risk of death. The median progression-free survival was 5.6 months in the Trodelvy group versus 1.7 months in the standard treatment group, which translates to a 59% reduction in the risk of disease progression or death. Trodelvy also increased the objective response rate (the percentage of patients who had a partial or complete shrinkage of their tumors) from 22% to 35%.

Based on these results, Trodelvy was approved by the US Food and Drug Administration (FDA) in 2020 and by the European Medicines Agency (EMA) in 2021 for the treatment of unresectable or metastatic triple-negative breast cancer in combination with endocrine therapy after disease progression following endocrine therapy.

However, Trodelvy is not without side effects. The most common adverse events of grade 3 or higher (severe or life-threatening) were neutropenia (low white blood cell count), diarrhea, anemia (low red blood cell count), fatigue, nausea, vomiting, alopecia (hair loss), and rash. These side effects can be managed with dose adjustments, supportive care, and monitoring.

Trodelvy is a novel and effective option for patients with unresectable or metastatic triple-negative breast cancer who have failed previous treatments. It offers a personalized approach that targets the specific protein that drives the disease. Trodelvy represents a new hope for this subgroup of patients who have limited treatment options and poor prognosis.