Roche Breast Cancer Drug Misses Late-Stage Study Goal

“Roche Holding shares fell Monday after the company said a late-stage study for an experimental breast-cancer treatment missed its primary objective.

 

The results of the clinical trial mark a setback for the Swiss pharmaceutical company, which saw in the drug, giredestrant, a candidate to become a blockbuster treatment. The drugmaker, though, said there was still a path forward for the medicine.

 

Shares of Roche finished 3% lower amid broad-based losses across European stocks due to the conflict in the Middle East and surging oil prices.

 

The decline wiped out most of the year-to-date gains in Roche's stock.

 

The pharmaceutical company said the combination of its investigational giredestrant with Pfizer's Ibrance didn't meet the primary objective of a statistically significant improvement in progression-free survival in patients with advanced breast cancer. In the late-stage trial, the combination was compared against a combination of Ibrance with Novartis's Femara.

 

Analysts at J.P. Morgan said the outcome of the trial would likely remove any potential sales of giredestrant as a first-line treatment for breast cancer, a market valued at nearly $10 billion. The results largely restrict the drug's use to the adjuvant setting, as a follow-up to surgery, which is a market valued at between $10 billion and $20 billion, the analysts said.

 

This was the first of two late-stage studies for giredestrant as a first-line treatment, Roche said. Results of the other study are due to be published next year, it said. The company's late-stage program for giredestrant includes five trials in total.

 

"We continue to be rather confident that there is an opportunity for giredestrant as a single agent and in combination," Roche's Deputy Chief Medical Officer Stefan Frings said in an interview.

 

In the company's most-recent results, executives at Roche said they were in the process of updating their own assumptions to provide an estimate for the peak sales potential of the drug.

 

The pharmaceutical company sees potential for sales to exceed 3 billion Swiss francs, or $3.87 billion, and analysts polled by Visible Alpha had forecast giredestrant sales of about 5.8 billion francs in 2034.

 

Roche said a numerical improvement in progression-free survival was observed in the trial, meaning the results were at least as good as those of the other drug combination, but not enough to call them superior.

 

The drug combination was well tolerated, with adverse events consistent with the known safety profiles of each treatment, the company added.

 

Giredestrant is designed to block estrogen -- a hormone that drives 70% of all breast-cancer cases -- from binding to receptors to stop or slow down the growth of cancer cells.

 

Last year, the company reported results from two studies that showed positive results as a second-line treatment -- when a first therapy has failed -- and as an adjuvant in early-stage breast cancer. But analysts said at the time results of the third trial as a first-line treatment would be key for the drug's commercial prospects.

 

Roche said it filed an application for giredestrant as a second-line treatment with the U.S. Food and Drug Administration, which was accepted, and that the company planned to submit another for the adjuvant setting in coming weeks.

 

Frings said those applications wouldn't be affected by the outcome of the latest study, given that they were supported from their own trials that achieved highly positive results.” [1]

 

1. Roche Breast Cancer Drug Misses Late-Stage Study Goal. Calatayud, Adria.  Wall Street Journal, Eastern edition; New York, N.Y.. 10 Mar 2026: B4.