Roche Breast Cancer Drug Delays Progression by Over Four Months
(Bloomberg) — Roche Holding Ag’s experimental drug giredestrant reduced the risk of breast cancer worsening by almost two thirds in some patients with an advanced form of the disease.
Patients in the trial were given Roche’s oral medicine giredestrant, combined with the immunosuppressant everolimus. In a group of patients with a specific genetic mutation called ESR1, the drug helped patients live about 4.5 months longer without their cancer worsening or them dying.
The data will change the way doctors treat patients, Charles Fuchs, Roche’s global head of oncology and hematology, said in an interview. “Physicians will make this a routine.”
The study shows that newer types of hormone therapies can outperform existing drugs that target estrogen, said Harold Burstein, a medical oncologist at Dana-Farber Cancer Institute. Burstein was not involved in the trial.
In the wider trial population, patients receiving the giredestrant combination lived 3.3 months longer without their cancer worsening, a 44% improvement over those receiving the current standard treatment. Fuchs said Roche believes the drug works both on patients with the ESR1 mutation and those without it.
Roche will share the data with regulators, aiming to bring the drug to market as soon as it can, it said in a statement Saturday.
The detailed trail results — presented at the European Society for Medical Oncology Congress in Berlin — follow positive high-level data released in September that was seen as a surprise given the difficulties faced by rivals.
It is not yet clear if the drug prolongs lives. Roche said a “clear positive trend was seen in both populations.” The study looked at patients with breast cancer known as ER-positive, HER2-negative that was either advanced or had spread.
Roche needs positive results from trials like this to convince investors about its future competitiveness. Giredestrant could reach over 1 billion Swiss francs ($1.3 billion) in sales in 2031, according to analysts surveyed by Bloomberg.
Roche has been seeking deals to boost its pipeline, particularly in the obesity space, recently announcing the acquisition of 89bio Inc. for $3.5 billion.
–With assistance from Naomi Kresge.
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