Sanofi winds $40m into UK gene therapy firm Gyroscope

French drugmaker Sanofi has made a $40 million investment in Gyroscope Therapeutics, with another $20 million potentially on offer as the UK biotech advances its clinical-stage gene therapies for ophthalmic diseases.

The investment gives Sanofi rights of first refusal on GT005, Gyrocope's lead gene therapy for geographic atrophy (GA) secondary to age-related macular degeneration (AMD), a major cause of blindness, in select geographies.

The deal will also see a Sanofi R&D executive join Gyroscope's board to provide advice on the development of GT005.

The gene therapy is currently being tested in phase 2 trials involving two different genetically defined patient populations with GA, an advanced form of 'dry' AMD affecting the central portion of the retina. At the moment there is no approved therapy for the disease, which affects around five million people globally.

GT005 is a one-shot therapy which aims to treat GA by delivering the gene for complement factor I (CFI) to the eye using an adeno-associated virus (AAV) vector. CFI regulates the activity of the complement immune system which is over-activated in GA.

Recent phase 1/2 data from the FOCUS trial of GT005 involving 28 patients found sustained increases in vitreous CFI in the eye, indicating the gene therapy was integrating as expected, along with reductions in biomarkers associated with GA.

There was no evidence of clinically significant GT005-induced inflammation, which is a perennial concern with gene therapies that involve viral vectors.

The two phase 2 studies – in patients with rare variants in the CFI gene (EXPLORE) as well as a broader group of people with GA secondary to AMD (HORIZON) – are due to generate results in 2022/2023.

The stake comes after Gyroscope raised $148 million earlier this year in third-round financing, but also after an aborted attempt to file an initial public offering in the US hoping to raise $100 million, which the company said was due to "market conditions."

Gyroscope is going up against some heavyweight competition in gene therapies for GA, so having a big pharma on board could be an asset for Gyroscope.

Rivals include Johnson & Johnson's pharma unit Janssen which bought rights to a gene therapy for the condition from Hemera Biosciences, as well as Novartis which acquired a GA project as part of its $280 million takeover of Vedere Bio last year.

First launched in 2016, Gyroscope expanded in 2019 when it merged with Orbit Biomedical to gain control of the latter's sub-retinal delivery technology.

At that time founding investor Syncona held 82% of the merged company with a book value of  around $38 million. Syncona said today its stake has now reduced to 49% and is worth around $208 million.