Gene therapy readout helps Ultragenyx rebound

Orphan disease company Ultragenyx added nearly $600 million in market cap Friday after reporting better-than-expected data for gene therapy DTX301 -- a welcome lift after clinical disappointments had weighed on the stock in 2H19.

After market close on Thursday, Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) reported initial data from the higher-dose third cohort of three patients in a Phase I/II trial of DTX301 to treat ornithine transcarbamylase (OTC) deficiency, a genetically driven urea cycle disorder that leads to the buildup of ammonia in the blood...