Biotechnology company Genentech, a member of the Roche Group (SIX: RO, ROG) (OTCQX: RHHBY), said on Tuesday that the US Food and Drug Administration (FDA) has accepted its New Drug Application under Priority Review for giredestrant as an adjuvant treatment for adults with ER-positive, HER2-negative stage I-III breast cancer.

The FDA has set a Prescription Drug User Fee Act decision date of 30 November 2026.

The filing is supported by Phase III lidERA study results showing that giredestrant reduced the risk of invasive disease recurrence or death by 30% compared with standard-of-care endocrine therapy, with 92.4% of patients alive and free of invasive disease at three years versus 89.6% for standard treatment.

Genentech said giredestrant was well tolerated, with a treatment discontinuation rate of 5.3% compared with 8.2% for standard-of-care endocrine therapy.

The company described giredestrant as the first oral selective oestrogen receptor degrader to deliver positive Phase III results in the curative setting and said it has the potential to become a new standard of care for ER-positive early-stage breast cancer.

The FDA has also accepted a separate application for giredestrant in combination with everolimus for ESR1-mutated, ER-positive advanced breast cancer, with a regulatory decision expected in December 2026.