Gilead Sciences has received the US Food and Drug Administration (FDA) full approval for its Trodelvy (sacituzumab govitecan-hziy) to treat metastatic triple-negative breast cancer (TNBC).

In April last year, Trodelvy has received accelerated approval in the US, based on objective response rate and duration of response results in a Phase 1/2 trial.

The current full approval expands its previous indication to include adults with metastatic TNBC, who received two or more prior treatments, at least one for metastatic disease.

Trodelvy is an antibody and topoisomerase inhibitor conjugate that targets Trop-2 receptor, a protein often expressed in different types of epithelial tumours, including metastatic TNBC.

The drug is also used as an investigational treatment for metastatic urothelial cancer, HR+/HER 2- metastatic breast cancer and metastatic non-small cell lung cancer (NSCLC).

Gilead Sciences chief medical officer Merdad Parsey said: “Today’s approval is the culmination of a multi-year development program and validates the clinical benefit of this important treatment in metastatic TNBC.

“Building upon this milestone, we are committed to advancing Trodelvy with worldwide regulatory authorities so that, pending their decision, Trodelvy may become available to many more people around the world who are facing this difficult-to-treat cancer.”

The FDA approval is based on data from the Phase 3 ASCENT study, an open-label, active-controlled, randomised confirmatory trial, which enrolled more than 500 patients.

Trodelvy showed a statistically significant and clinically meaningful reduction in the risk of disease worsening or death, also called progression-free survival (PFS) by 57%.

The drug has extended median PFS to 4.8 months from 1.7 months with chemotherapy along with median overall survival (OS) to 11.8 months, reducing the risk of death by 49%.

Trodelvy showed a safety profile consistent with the previously approved FDA label.

In the clinical trial, Trodelvy met the primary efficacy outcome of PFS, and additional efficacy measures of PFS for the full population and OS, said the company.

ASCENT study global principal investigator Aditya Bardia said: “Women with triple-negative breast cancer have historically had very few effective treatment options and faced a poor prognosis.

“Today’s FDA approval reflects the statistically significant survival benefit seen in the landmark ASCENT study and positions sacituzumab govitecan-hziy as a potential standard of care for pre-treated TNBC.”

Last year, Gilead acquired antibody-drug conjugates (ADC) company Immunomedics, which originally developed Trodelvy, for a total of $21bn.

The company has filed regulatory submissions for Trodelvy in metastatic TNBC, in the UK, Canada, Switzerland and Australia as part of the FDA’s Project Orbis initiative.