Nightstar Therapeutics plc,. (NASDAQ: NITE), has reported that an acquisition agreement with Biogen is to be completed in mid-year 2019 for an estimated $877M.  Nightstar was a UK based spin-out of the University of Oxford, based on the founding work of Professor Robert MacLaren at the Nuffield Laboratory of Ophthalmology.  The company recently announced the receipt of Regenerative Medicine Advanced Therapy (RMAT) designation from the US FDA.  The RMAT designation, established under the 21st Century Cures Act, is an expedited program for the advancement and approval of regenerative medicine products benefiting the sponsors of treatments for serious or life-threatening diseases through closer and more frequent interaction with the FDA, including eligibility for priority review and accelerated approval. Following of the orphan designation work, the company built a valuable proposition which recently now intends to progress further in rare disease clinical trials.

Nightstar’s RMAT designation from the FDA is for the development of NSR-REP1, the company’s lead product candidate currently in Phase III development for the treatment of choroideremia. Choroideremia is a rare X-linked disease caused by mutations in the CHM gene, a transcript encoding the REP1 protein which functions in intracellular protein trafficking and waste disposal in retinal cells.  The disorder afflicts approximately 1 in 50,000 people primarily affecting male patients and is usually diagnosed in childhood.  Dysfunctional REP1 often leads to cell apoptosis causing progressive vision loss and blindness from an early age making the condition a devastating long-term illness.  NSR-REP1 is the company’s lead clinical-stage product comprised of an AAV2 vector housing a functional cDNA for the production of REP1 inside the eye, designed to rescue the cells from the primary genetic lesion.   In preliminary studies of  32 patients treated with NSR-REP1 across four open-label Phase I / II clinical trials, 90%+ of treated patients maintained visual acuity over a two-year follow-up period.

After the acquisition of the company, David Fellows, Chief Executive Officer of Nightstar, said: “Our agreement with Biogen will give us the platform and resources to expand our mission to maintain and restore sight in patients with inherited retinal diseases. This transaction accelerates treatment to patients through Nightstar’s key retinal gene therapy programs that modify or halt progression of blindness. Together, with Biogen’s expertise in rare diseases, worldwide reach and extensive resources, we will dramatically improve the lives of patients around the world who currently have no treatment options. We are proud of what Nightstar has accomplished, and we thank our team for their tireless work to improve the lives of our patients and their families.”