Vertex Falls After FDA Halts Diabetes Study in Surprise Move

Vertex Pharmaceuticals Inc. tumbled after U.S. regulators placed its study of a key new treatment for type 1 diabetes on clinical hold.

The Food and Drug Administration paused the early-stage study after determining that there is insufficient evidence to support increasing dosage of the product, VX-880, Vertex said Monday in a statement. The drugmaker said it’s “surprised” by the decision because findings have been promising in the first two patients treated with half of the target dose.