Biogen Completes Acquisition of Nightstar Therapeutics for Approximately $800 Million

Biogen announced that it has completed its acquisition of Nightstar Therapeutics, a clinical-stage gene therapy company, which is focused on adeno-associated virus (AAV) treatments for inherited retinal disorders. As a result of the acquisition, Biogen now has added two mid- to late-stage clinical assets, as well as preclinical programs, in ophthalmology. The total transaction value was approximately $800 million, after taking into account expected transaction expenses and cash at closing. NST’s common stock will no longer be listed for trading on the Nasdaq Global Select Market.

NST’s lead asset is NSR-REP1 for the treatment of choroideremia (CHM), a rare, degenerative, X-linked inherited retinal disorder, which leads to blindness and has no approved treatments. CHM primarily affects males and is caused by loss of function in the CHM gene which encodes the Rab escort protein-1 (REP-1). Initially, patients with CHM experience poor night vision, and over time progressive visual loss ultimately leads to complete blindness.

NSR-RPGR is NST’s second clinical program for the treatment of X-linked retinitis pigmentosa (XLRP), which is also a rare inherited retinal disease primarily affecting males with no approved treatments. XLRP is characterized by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene leading to a lack of active protein transport in photoreceptors. This abnormality leads to loss of photoreceptor cells, resulting in retinal dysfunction by adolescence and early adulthood, progressing to legal blindness when patients reach their 40s.

“Today marks a significant achievement for Biogen,” said Michel Vounatsos, Biogen’s Chief Executive Officer. “The acquisition of Nightstar further bolsters our pipeline and is an important step forward toward our goal of a multi-franchise portfolio across complementary modalities. We look forward to working now as one Biogen team with the goal of bringing breakthrough therapies to patients to slow or halt blindness across a range of inherited retinal diseases.”

Goldman, Sachs & Co. acted as financial advisor to Biogen, and Ropes & Gray LLP acted as legal counsel.

Centerview Partners acted as financial advisor to NST, and Skadden, Arps, Slate, Meagher & Flom LLP acted as legal counsel.