BOSTON, Massachusetts, Nov. 27 -- Ropes and Gray, a law firm, issued the following news: * * * Ropes & Gray advised long-time client Sarepta Therapeutics in a transformational global licensing and collaboration agreement with Arrowhead Pharmaceuticals for multiple siRNA programs. Sarepta will obtain exclusive worldwide rights to four clinical stage and three preclinical stage programs targeting muscle, nervous system and rare pulmonary disorders, as well as rights to use Arrowhead's novel disc more PR