Results from the Breast Cancer Research Foundation investigator-led clinical trials underpin approvals
Key takeaways
- These approvals give doctors more treatment options for patients with mTNBC.
- Because mTNBC is aggressive and fast-growing, choosing a powerful first-line treatment is critical. Trodelvy’s efficacy as a first-line treatment may improve outcomes, providing a profound impact on patients’ lives.
- This targeted ADC outperforms chemotherapy, sparing patients its short- and long-term effects.
The U.S. Food & Drug Administration (FDA) approved the antibody-drug conjugate (ADC) sacituzumab govitecan (SG/Trodelvy) for two indications in patients with metastatic triple-negative breast cancer (mTNBC). These approvals are practice-changing for these patients that face an aggressive form of the disease that has had few therapeutic options.
Triple-negative breast cancer lacks three key treatment targets, estrogen and progesterone receptors and HER2 protein. It is an aggressive form that is generally treated systemically with chemotherapy and in some cases, PARP inhibitors or immunotherapy. Because chemotherapy causes short- and long-term side effects and immunotherapy has had limited success, researchers are working to expand the treatment options and devising new strategies to treat TNBC. The FDA’s approval of Trodelvy adds a powerful treatment option to a small list of therapies approved for the disease that is difficult to treat.
Trodelvy is a targeted treatment which recognizes and binds to TROP2—a protein often found on TNBC cells—and delivers a drug that is toxic to cells, (topoisomerase inhibitor) directly to cancer cells. The new FDA approvals for Trodelvyare practice-changing and based on the results of clinical trials led by BCRF investigators.
- ASCENT03: Trodelvy achieved progression-free survival of six to nine months longer compared to chemotherapy in patients with mTNBC not eligible for immunotherapy.
These results support its use as a single agent for the first-line treatment of these patients. - ASCENT04: Trodelvy plus immunotherapy (pembrolizumab/Keytruda) demonstrated a progression-free survival of 14 months longer compared to chemotherapy plus immunotherapy. Pembrolizumab is a PD-L1 inhibitor, a type of immunotherapy drug that blocks the PD-L1 protein, which cancer cells use to “hide” from the immune system. Based on ASCENT04, the SG combination is now approved for the first-line treatment of patients with mTNBC who are eligible for immunotherapy i.e., their tumors express PD-L1.
Importantly, Trodelvy outperformed chemotherapy in both trials, reducing the risk of disease progression by about 35% when compared with chemotherapy.
What this means for patients
This news helps expand the arsenal of treatments in the first-line setting for the type of breast cancer; TNBC’s aggressive and fast-growing nature make the choice of first-line treatment particularly critical. The new approvals signal a practice-changing era where patients may be spared chemotherapy and its potentially lingering effects.
