By Adria Calatayud


Roche Holding shares fell 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 generate annual peak sales above 3 billion Swiss francs ($3.87 billion). The drugmaker, though, said there was still a path forward for the medicine.

Shares in Roche fell as much as 8% in early morning trade Monday, amid broad-based losses across European stocks due to the conflict in the Middle East and surging oil prices, before recovering somewhat. The decline wiped out the year-to-date gains in Roche's stock.

The 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--and largely restrict its use to the adjuvant setting, as an additional treatment after patients have already received an initial therapy--a market valued at between $10 billion and $20 billion.

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.

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, it 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 it 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.


Write to Adria Calatayud at adria.calatayud@wsj.com


Corrections & Amplifications

This was corrected at 11:31 a.m. ET because the original version incorrectly said analysts at J.P. Morgan said the outcome of Roche's trial would largely restrict giredestrant's use to the adjuvant setting, a market valued at between $10 million and $20 million.

(END) Dow Jones Newswires

03-09-26 0551ET