A new drug shows efficacy against advanced endometrial cancer, according to a phase 3 trial

The article is of high quality. TroFuse-005 is a randomized, multicenter, phase III trial comparing sacituzumab tirumotecan (Sac-TMT)—a novel antibody-drug conjugate targeting TROP2—with chemotherapy monotherapy, which has historically been one of the standard treatment options in this setting.

The TROP2 protein, the target of this new antibody-drug conjugate, is highly expressed in various tumors, including endometrial cancer.

These findings are significant because, for the first time in a phase III trial, they demonstrate that a new therapy improves both progression-free survival and overall survival in patients with advanced or recurrent endometrial cancer whose disease has progressed following prior chemotherapy and immunotherapy. This is a patient population with limited therapeutic options and a substantial unmet medical need. With conventional chemotherapy, response rates are low—around 15%—and overall survival is typically less than one year.

Sac-TMT reduces the risk of disease progression or death by 41% (hazard ratio [HR] 0.59), with a median progression-free survival of 7.2 months, compared to 3.9 months with chemotherapy. Furthermore, it reduces the risk of death by 32% (HR 0.68), with a median overall survival of 19 months, compared to 12.1 months.

These results are sufficiently robust to shift clinical practice and establish Sac-TMT as a new standard of care for patients with relapsed endometrial cancer whose disease has progressed after chemotherapy and immunotherapy.

Sac-TMT is also being investigated in earlier stages of the disease—specifically as a maintenance therapy in combination with pembrolizumab—for patients with advanced or recurrent endometrial cancer. [Regarding potential limitations] Sac-TMT presents a toxicity profile that requires specific prevention and management strategies, particularly for adverse effects such as stomatitis and ocular complications. It will be essential to identify these effects early and implement preventive measures—such as the use of ocular lubricants and oral rinses—to maintain the patients' quality of life.

The incidence of endometrial cancer has been rising in recent years. For patients diagnosed at an advanced stage, the prognosis is poor, with a progression-free survival of approximately 13 months when treated with standard chemotherapy (carboplatin and paclitaxel). The combination of immunotherapy and chemotherapy has shifted the treatment paradigm for advanced endometrial cancer, substantially increasing overall survival—particularly in patients with dMMR tumors (tumors with a deficiency in DNA mismatch repair).

However, the integration of immunotherapy into the first-line treatment setting has created an unmet need in subsequent lines of therapy. If the cancer progresses following chemo-immunotherapy, therapeutic options become limited, often restricted to single-agent chemotherapy, which yields response rates of less than 20%. In this context, SAC-TMT has demonstrated a clinically and statistically significant improvement in both progression-free survival and overall survival compared to conventional chemotherapy in patients with advanced or recurrent endometrial cancer that has progressed after platinum-based chemotherapy and immunotherapy, all while maintaining a tolerable safety profile. SAC-TMT is emerging as a standard-of-care treatment for this patient population, though careful consideration must be given to the drug’s toxicity and the fact that the follow-up period remains relatively short.