Alnylam shares drop 1.8% on new FDA approval strategy for rare disease drug

Alnylam Pharmaceuticals Inc. shares dropped 1.8% in Monday premarket trade after the company announced that it intends to apply for full U.S. approval of its rare disease drug, rather than a faster-than-usual approval, signifying a more extended approval timeline for the therapy. The drug, givosiran, is currently in a phase 3 clinical trial, with preliminary results expected in early 2019. Alnylam plans to submit a "rolling" new drug application with the Food and Drug Administration starting this year, with full clinical trial results from the phase 3 trial to be submitted in mid-2019.