Ultragenyx Tumbles After Setrusumab Fails Two Trials

The Ultragenyx biomanufacturing plant in Bedford, Massachusetts.

Photographer: Jonathan Wiggs/The Boston Globe/Getty Images

Ultragenyx Pharmaceutical Inc. sank after the company’s experimental drug for a rare genetic bone disease failed to meet the primary endpoints in two phase 3 clinical trials.

Ultragenyx dropped 41% at 10 a.m. in New York Monday. Its shares had fallen 19% year to date through the close on Dec. 26.