Gilead’s Trodelvy can now be used as a monotherapy and in combination with Merck’s Keytruda to treat certain patients with triple-negative breast cancer.
The FDA has given its go-ahead to Gilead’s anti-TROP-2 antibody-drug conjugate Trodelvy as a frontline option for two specific triple-negative breast cancer indications.
With the approvals, announced Wednesday, Trodelvy can now be used as a monotherapy for patients with unresectable locally advanced or metastatic triple-negative breast cancer (mTNBC) who are ineligible for PD-1 or PD-L1 therapies. Gilead’s product can now also be given alongside Merck’s Keytruda or Keytruda Qlex to treat TNBC patients whose tumors express PD-L1.
“For more than twenty years, patients with mTNBC have had limited choices in first-line treatment,” Gilead CMO Dietmar Berger said in a company statement announcing the approval. By expanding into this setting, Trodelvy “provides a new standard of care for the most aggressive form of breast cancer,” he said.
Data from the Phase 3 ASCENT-03 and ASCENT-04 studies underpinned the FDA approvals. In the former trial, treatment with Trodelvy resulted in median progression-free survival (PFS) of 9.7 months versus 6.9 months in controls on a standard anti-cancer regimen—a significant 38% reduction in the risk of death or disease progression. Confirmed objective response rate (ORR) was 50% in the Trodelvy group versus 47% in controls, according to the FDA release.
Meanwhile, ASCENT-04 enrolled nearly 450 patients who were randomly assigned to receive a regimen of Trodelvy and Keytruda or standard chemotherapy. Those who received the Merck/Gilead combo saw a median PFS of 11.2 months versus 7.8 months in controls. This corresponded with a 35% decrease in the risk of death or disease progression.
Wednesday’s approval marks a comeback for Merck and Gilead’s campaign to combine Trodelvy with Keytruda. Earlier this month, the partners pulled the plug on the Phase 3 KEYNOTE-D46 study, which was evaluating a regimen of the two therapies for patients with non-small cell lung cancer who are positive for PD-L1 expression.
An independent data committee found the study would be “unlikely” to hit its key efficacy goal of improving overall survival, the companies said at the time.
Trodelvy’s first-line expansion puts it on more even ground with AstraZeneca and Daiichi Sankyo’s Datroway, which last month was approved for frontline mTNBC in patients who are ineligible for PD-1/PD-L1 inhibitor treatment.
