PARIS (Reuters) – Sanofi will pay Regeneron some $462 million in a revision of their deal in immuno-oncology, a growing sector in healthcare research which aims to help the body’s own immune system fight cancer.

The two companies said the new arrangement would give France’s Sanofi increased flexibility to advance its early-stage immuno-oncology pipeline, while U.S. healthcare group Regeneron retains all rights to its other immuno-oncology discovery and development programmes.

Sanofi will pay Regeneron $462 million representing the balance of payments due under their original deal, which covers the Sanofi share of the immuno-oncology discovery programme costs for the last quarter of 2018. The payment includes up to $120 million in other development costs.

Sanofi shares fell 1.1 percent in early session trading.

For its part, Regeneron will commit up to $120 million to fund new developments in the field.

Sanofi and Regeneron also work together on the development of the Dupixent product which is used to treat eczema, and which has had positive feedback from U.S. regulators.

(This story corrects to make clear that the price is about $462 million as other development costs are included in the amount)

(Reporting by Sudip Kar-Gupta; Editing by Jane Merriman and Alexander Smith)