CAMBRIDGE, Mass.—Biogen recently announced an agreement to acquire London-based Nightstar Therapeutics, a clinical-stage gene therapy company focused on adeno-associated virus (AAV) treatments for inherited retinal disorders. Under the terms of the proposed acquisition, Biogen will pay $25.50 in cash for each Nightstar share.
“Biogen continues its diversification strategy through the acquisition of Nightstar Therapeutics. The deal will allow Biogen to catapult itself into the ophthalmology market, a new segment which the company had been chasing to enter in the past already. Although the deal will not have an immediate impact on Biogen’s bottom line, as Nightstar is a clinical-stage company, it will inherit its pipeline of rare inherited retinal diseases,” explained Maura Musciacco, director of neurology and ophthalmology at data and analysis firm GlobalData. “Notably, this deal comes only one week after Roche’s acquisition of Spark Therapeutics, another gene therapy specialist, and less than a year ago, Novartis also showed interest in building its gene therapy portfolio through its acquisition of AveXis. Despite being a field typically associated with small specialist players, the recent news is a strong sign that big pharma is ready to splash the cash and pay significant premiums to expand its rare disease offering.”
The offer represents a total transaction value of approximately $800 million, after taking into account expected transaction expenses and anticipated cash at closing. The acquisition of Nightstar is planned to be funded through available cash and accounted for as an acquisition of a business. Biogen expects to complete the acquisition by mid-year 2019.
“Ophthalmology is an emerging growth area for Biogen, and we are excited about the opportunity to work with the talented employees at Nightstar to advance potentially transformative gene therapy programs for rare retinal diseases,” said Michel Vounatsos, CEO of Biogen. “With this proposed acquisition, we are continuing to bolster our pipeline and further execute on our strategy to develop and expand a multi-franchise neuroscience pipeline across complementary modalities. Nightstar would accelerate our entry into ophthalmology by contributing two mid- to late-stage gene therapy assets, with the potential to create long-term shareholder value.”
Nightstar’s lead asset is NSR-REP1 for the treatment of choroideremia (CHM), a rare degenerative X-linked inherited retinal disorder which primarily affects males and is caused by loss of function in the CHM gene which encodes the Rab escort protein-1 (REP-1). The REP-1 protein plays a role in intracellular protein trafficking, and loss of function in the CHM gene leads to abnormal intracellular protein trafficking and impaired elimination of waste products from the retinal pigment epithelium and photoreceptors. Initially patients with CHM experience poor night vision, and over time progressive visual loss leads to complete blindness.
NSR-REP1 is an AAV vector administered by subretinal injection which provides a functioning CHM gene and expression of the REP-1 protein to restore membrane trafficking and slow, stop or potentially reverse the decline in vision. Data from the Phase 1/2 trial of NSR-REP1 demonstrated potentially meaningful slowing of decline in visual acuity as compared to natural history, as well as signs of improved visual acuity in some patients. NSR-REP1 is currently being evaluated in the ongoing Phase 3 STAR trial, with data expected in the second half of 2020.
“Both of the lead clinical programs for NITE are intending to treat serious inherited blinding diseases of the eye and both have established initial proof of concept, but are still two to four years away from commercialization. The most advanced of these programs could launch by 2022, assuming clinical development and regulatory timelines are maintained. The final profile and potential of these programs will depend on the results of their pivotal trials,” noted a report by SVB Leerink. “We believe the inherent difficulties in patient identification in choroideremia and XLRS, as well as the logistical constraints associated with a subretinal injection, may dampen the commercial opportunity for such transformative medicines.”
Nightstar’s second clinical program is NSR-RPGR for the treatment of X-linked retinitis pigmentosa (XLRP), also a rare inherited retinal disease primarily affecting males. XLRP is characterized by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene, and a lack of active protein transport in photoreceptors. This leads to loss of photoreceptor cells, resulting in retinal dysfunction by adolescence and early adulthood, and progressing to legal blindness when patients reach their 40s.
NSR-RPGR is also a subretinal injection of an AAV vector, which provides a functioning RPGR gene and expression of the RPGR protein. The restoration of photoreceptor function is intended to slow, stop or potentially reverse the decline in vision. Phase 1/2 data from the dose escalation portion of the XIRIUS trial for NSR-RPGR demonstrated an increase in central retinal sensitivity. The Phase 2/3 dose expansion portion of the XIRIUS trial is currently ongoing.
Nightstar’s preclinical pipeline includes NSR-ABCA4 for Stargardt disease, and potential programs targeting Best vitelliform macular dystrophy (Best disease) and other genetic forms of retinitis pigmentosa.