Gilead's Trodelvy Scores Dual Victories in Breast Cancer Trials, Bolstering First-Line Potential

Gilead Sciences' antibody-drug conjugate (ADC) Trodelvy has demonstrated significant efficacy in two separate clinical trials for metastatic triple-negative breast cancer (TNBC), potentially expanding its role as a first-line treatment option.

ASCENT-03 Trial: Trodelvy Outperforms Chemotherapy in Solo Study

In the late-stage ASCENT-03 trial, Trodelvy (sacituzumab govitecan) showed superior results compared to standard-of-care chemotherapy in extending progression-free survival (PFS) for previously untreated metastatic TNBC patients. The study focused on patients who are not candidates for PD-1 or PD-L1 inhibitors, either due to low PD-L1 expression or ineligibility for immunotherapy.

Gilead reported that the improvement in PFS was both "highly statistically significant and clinically meaningful," meeting the trial's primary endpoint. The company plans to present detailed results at an upcoming medical conference and discuss the findings with regulatory authorities.

Dr. Dietmar Berger, Gilead's Chief Medical Officer, emphasized the significance of the results, stating, "The ASCENT-03 outcome represents the first clinically meaningful advance for this patient population in over 20 years versus chemotherapy."

ASCENT-04 Trial: Trodelvy-Keytruda Combination Shows Promise

The ASCENT-03 results follow closely on the heels of positive data from the ASCENT-04 trial, where Trodelvy was combined with Merck & Co.'s Keytruda (pembrolizumab). This combination therapy demonstrated superior PFS compared to Keytruda plus chemotherapy in previously untreated TNBC patients with PD-L1-expressing tumors.

Gilead is set to present detailed results from ASCENT-04 at the upcoming American Society of Clinical Oncology (ASCO) meeting.

Implications for Trodelvy's Market Position

These trial successes come at a crucial time for Trodelvy, as it faces increasing competition from new TROP2-targeted ADCs. AstraZeneca and Daiichi Sankyo's Datroway (datopotamab deruxtecan) recently gained FDA approval for HR-positive, HER2-negative breast cancer, while Kelun-Biotech's sacituzumab tirumotecan has been approved in China.

Despite recent setbacks in other clinical trials, Gilead remains optimistic about Trodelvy's potential. The company believes that with positive data in both PD-L1-positive and PD-L1-negative breast cancer patients, Trodelvy "has the potential to be the backbone treatment for all patients across first-line mTNBC."

Trodelvy generated $1.3 billion in sales for 2024, representing a 24% year-over-year growth. Analysts currently project peak sales potential of $2.9 billion to $3.2 billion by 2030, underscoring the drug's importance to Gilead's oncology portfolio.