Regeneron Pharmaceuticals Inc.'s suptavumab failed to meet its primary endpoint of preventing respiratory syncytial virus infections in preterm infants in a phase 3 study.

The infection known as RSV is a common virus that leads to cold-like symptoms in adults but can be more serious in young infants. Suptavumab is an antibody to RSV.

Regeneron plans to discontinue further clinical development for the treatment, the company said in a news release.