Roche has announced that the US Food and Drug Administration (FDA) has accepted and granted priority review to a supplemental Biologics License Application (sBLA) for Enspryng (satralizumab) as a potential treatment for thyroid eye disease (TED).
TED, also known as Graves’ ophthalmopathy, is a rare autoimmune inflammatory disease that affects the area around the eyes and the eyes themselves, which can be sight-threatening, debilitating and disfiguring. The most common symptoms associated with the condition include redness and swelling of the eyes, eyelid retraction, a staring appearance, bulging eyes (proptosis), double vision (diplopia), and pain.
The condition affects an estimated 155 people per 100,000 and is most commonly linked to hyperthyroidism, with around half of those patients experiencing at least mild TED. However, TED can also occur in people with hypothyroidism or normal thyroid function.
Although approved therapies are available, there remains a need for treatments that are effective, well tolerated and easier for patients to access and administer.
The FDA’s acceptance of the filing is supported by findings from Roche’s global phase III SatraGO programme, comprising two randomised, placebo-controlled studies evaluating the safety and efficacy of Enspryng in patients with moderate to severe TED. A regulatory decision is expected by 15 October 2026.
Levi Garraway, Roche’s Chief Medical Officer and Head of Global Product Development, welcomed the FDA’s decision as an important milestone in expanding treatment options for people living with thyroid eye disease.
“By targeting the underlying disease biology with a novel mechanism of action, this subcutaneous therapy has the potential to introduce a new treatment approach that combines clinical efficacy and a favourable safety profile with the convenience of at-home administration,” Garraway said.
Data from the pivotal SatraGO studies showed clinically meaningful improvements across key signs and symptoms of TED, alongside a favourable and differentiated safety profile compared with currently available treatment options.
In SatraGO-2, 53 per cent of patients treated with Enspryng achieved a proptosis reduction at week 24 compared to 23 per cent in the placebo group.
In SatraGO-1, 49 per cent of patients receiving Enspryng achieved a proptosis response versus 31 per cent in the placebo arm.
Across both studies, Enspryng also demonstrated notable improvements in secondary measures. Between 78 and 90 per cent of patients with active TED achieved reductions in Clinical Activity Score (CAS), while improvements in double vision were seen in 44 to 61 per cent of patients in SatraGO-1 and SatraGO-2.
About Enspryng (satralizumab)
Developed by Chugai, a member of the Roche Group, Enspryng is a humanised monoclonal antibody designed to target the IL-6 receptor, a key driver of inflammation. The therapy uses recycling antibody technology intended to maintain prolonged IL-6 inhibition and sustained suppression of inflammatory pathways.
Enspryng is currently approved in around 90 countries for the treatment of neuromyelitis optica spectrum disorder (NMOSD), including the United States and the European Union.
Roche is also advancing the development of Enspryng in additional autoimmune and inflammatory neurological conditions, including autoimmune encephalitis (AIE) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). The company recently reported positive phase III results in MOGAD and plans to submit regulatory applications later this year.
Enspryng has orphan drug designation in the US and EU for NMOSD and investigational orphan drug designation in the US for MOGAD, anti-NMDA receptor autoimmune encephalitis, and leucine-rich glioma-inactivated 1 autoimmune encephalitis.
