Gilead’s Trodelvy stumbles in key breast cancer study

US biotech Gilead Sciences (Nasdaq: GILD) has suffered another disappointment for its cancer therapy Trodelvy (sacituzumab govitecan-hziy), after the Trop-2-directed antibody-drug conjugate failed to meet its primary goal in the Phase III ASCENT-07 trial. Shares in Gilead slipped around 4% on Friday following the announcement.

The study tested Trodelvy as a first-line treatment after endocrine therapy in 654 patients with locally advanced, inoperable, or HR-positive/HER2-negative metastatic breast cancer. It did not significantly delay disease progression versus physician’s choice chemotherapy, missing the primary endpoint of progression-free survival as assessed by blinded independent central review. However, the company said there was an early trend toward improved overall survival, which will be tracked as data mature.

Chief medical officer Dr Dietmar Berger said Trodelvy remains a standard of care for pre-treated HR-positive/HER2-negative metastatic breast cancer based on the overall survival benefits seen in the earlier TROPiCS-02 study. Safety findings in ASCENT-07 were consistent with previous trials, with no new safety issues observed.