Gilead's breast cancer drug gets U.S. FDA approval for third indication

FILE PHOTO: A Gilead Sciences, Inc. office is shown in Foster City, California

By Raghav Mahobe and Bhanvi Satija

(Reuters) - Gilead Sciences said on Friday the U.S. Food and Drug Administration had greenlighted the use of Trodelvy for a third indication, providing another treatment option for patients with the most common type of breast cancer.

The drug was approved for an advanced form of breast cancer with a subtype known as HR-positive/HER2-negative in patients, who had stopped responding to a hormone-based therapy and at least two earlier systemic therapies.

Gilead's Trodelvy will likely face competition from AstraZeneca-Daiichi Sankyo's Enhertu, which is approved to treat breast cancer patients with HER2-low type, a subset of HER2-negative breast cancer.

While analysts said the expanded approval was "widely expected", Cowen's Tyler Van Buren told Reuters ahead of the decision that he expected demand for Trodelvy to be "pretty modest", as the survival rate in patients was lower compared to Enhertu.

Buren expects peak sales of $600 million for the drug in this indication.

Sales of the drug, already approved for a type of breast and bladder cancer in the United States, nearly doubled to $680 million in 2022 from $380 million a year earlier. Analysts on average expect Trodelvy sales to reach $955.3 million in 2023, according to Refinitiv.

Trodelvy sales have nearly doubled in a year

Gilead, which acquired the therapy as part of its $21 billion buyout of Immunomedics in 2020, estimates about 6,000-8,000 U.S. patients will be annually eligible for Trodelvy with the expanded approval.

Chief Medical Officer Merdad Parsey told Reuters ahead of the approval that Trodelvy provided a "really important option" for the late-stage breast cancer with HR-positive/HER2-negative type in patients, who do not have any other effective option.

Trodelvy works by targeting the cell surface antigen known as Trop-2 on cancer cells and belongs to a class of drugs known as antibody-drug conjugates.

(Reporting by Raghav Mahobe and Bhanvi Satija in Bengaluru; Editing by Shinjini Ganguli)