Biogen has completed its previously announced acquisition of Nightstar Therapeutics (NST), a clinical-stage gene therapy company based in London, for a total transaction value of approximately $800 million, taking into account expected transaction expenses and cash at closing.

NST specializes in adeno-associated virus (AAV) treatments for inherited retinal disorders. As a result of the acquisition, Biogen has added two mid-to-late stage clinical assets and preclinical programs in ophthalmology.

NST’s lead asset is NSR-REP1 for treating choroideremia (CHM), a rare degenerative, x-linked inherited retinal disorder, which leads to blindness, and which currently has no approved treatments, according to information from Biogen. CHM primarily affects males and is caused by a loss of function in the CHM gene, which encodes the Rab escort protein (REP-1).

Source: Biogen