California's Ionis Pharmaceuticals Inc. closed an expanded collaboration with Biogen Inc., after receiving clearance under the Hart-Scott-Rodino Act.
The companies, which amended the agreement in April, will develop novel antisense drugs for neurological diseases.
Massachusetts-based Biogen paid $1 billion in cash for the deal — $375 million up front and $625 million to buy 11,501,153 Ionis common shares at $54.34 each.
The collaboration builds on a previous agreement to develop Spinraza, a treatment for spinal muscular atrophy.
