Roche has announced that the US Food and Drug Administration (FDA) has accepted and granted Priority Review to the supplemental Biologics License Application (sBLA) for Enspryng (satralizumab) as a treatment for Thyroid Eye Disease (TED).

The regulatory submission is supported by data from the global Phase 3 SatraGO-1 and SatraGO-2 clinical trials, which evaluated the safety and efficacy of Enspryng in patients with moderate to severe TED. The findings were presented at the American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) meeting in October 2025. The FDA is expected to announce its decision on the application by October 15, 2026.

According to Roche, the Phase 3 programme demonstrated that Enspryng delivered clinically meaningful improvements across key signs and symptoms of thyroid eye disease while maintaining a favourable safety profile compared with currently available therapies.

In the SatraGO-2 trial, the therapy met its primary endpoint, with 53 percent of patients receiving Enspryng achieving a clinically significant reduction in proptosis (eye bulging) at Week 24, compared with 23 percent in the placebo group. In the SatraGO-1 study, 49 percent of patients treated with Enspryng achieved a proptosis response versus 31 percent in the placebo arm. Although the latter did not reach statistical significance, Roche said the study provides additional evidence supporting the therapy's potential benefit.

The treatment also demonstrated positive results across several secondary endpoints. Between 78 percent and 90 percent of patients with active TED experienced improvements in Clinical Activity Score (CAS), while 44 percent to 61 percent showed improvements in double vision (diplopia) across the two Phase 3 studies.

Roche reported that no new safety concerns were identified during the trials. The safety profile of Enspryng remained consistent with its established use in treating Neuromyelitis Optica Spectrum Disorder (NMOSD).

Levi Garraway, Chief Medical Officer and Head of Global Product Development at Roche, said the FDA's Priority Review marks an important milestone in expanding treatment options for people living with thyroid eye disease. He noted that Enspryng targets the underlying disease biology through a novel mechanism of action while offering the convenience of subcutaneous, at-home administration alongside a favourable safety profile.

If approved, Enspryng could become a new treatment option for patients with thyroid eye disease, offering an alternative approach to managing the autoimmune condition that affects the tissues surrounding the eyes.