RegenxBio won't match Ultragenyx's Dimension offer

Gene therapy company Dimension Therapeutics Inc. (NASDAQ:DMTX) said it regards a takeout offer from rare disease company Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) as superior to its existing merger agreement with RegenxBio Inc. (NASDAQ:RGNX), and that RegenxBio will not seek to match or exceed Ultragenyx's offer of $6 per share, or about $151 million.

In August, RegenxBio agreed to acquire Dimension in a stock deal with an implied value of $3.41 per Dimension share. In September, Ultragenyx countered with an offer of $5.50 per share in cash, and has since sweetened its offer. The $6-per-share price is a 400% premium to Dimension's close of $1.20 on Aug. 24, the day before it announced the RegenxBio deal (see BioCentury Extra, Aug. 25 & Sept. 18)...