Israel's Teva Pharmaceutical Industries and French drugmaker Sanofi said a study of a drug to treat ulcerative colitis and Crohn's disease showed it had met primary goals.

Teva and Sanofi said last year they would collaborate on developing a treatment for inflammatory bowel disease (IBD), hoping it will become a blockbuster drug - or one that generates annual sales of at least $1 billion.

Sanofi, a leader in immunology, had said it will invest $1.5 billion in the development of Teva's anti-TL1A drug undergoing phase 2 trials.

In the 14-week phase 2b study by Sanofi and Teva's U.S. affiliate held in the U.S., Europe and Israel, the drug, called duvakitug, showed that 36.2% of low dose and 47.8% of high dose patients achieved clinical remission compared with 20.45% on a placebo.

The companies said the treatment was consistent across subgroups and that this was the first and only randomized, placebo-controlled study to evaluate the impact of a TL1A antibody in Crohn's disease.

“The results from the ... study have exceeded our expectations," said Eric Hughes, head of global R&D and chief medical officer at Teva.

Detailed results are expected to be presented at a scientific forum in 2025.

Teva and Sanofi said duvakitug was generally well tolerated in both ulcerative colitis and Crohn's disease "with no safety signal identified."

"These unprecedented results show that duvakitug could represent the next frontier in treating ulcerative colitis and Crohn’s disease. If the magnitude of effect persists in the Phase 3 programme, we believe we will have a differentiated medicine for IBD patients who are in urgent need of new options,” said Houman Ashrafian, Sanofi's head of R&D.

The efficacy and safety of the drug have not yet been evaluated by any regulatory authority, they said.

Sanofi and Teva said they plan to initiate phase 3 development in inflammatory bowel disease, pending regulatory discussions. They noted that there currently is no cure for IBD.

Both companies will equally share the development costs globally and net profits and losses in major markets, with other markets subject to a royalty arrangement. Sanofi will lead the development of the phase 3 clinical trials.

Teva will lead commercialization of the product in Europe, Israel and specified other countries, and Sanofi will lead commercialization in North America, Japan, other parts of Asia and the rest of the world.