FDA Approves Roche’s Enspryng as First At-Home Subcutaneous Treatment for Thyroid Eye Disease

The FDA has approved Roche’s satralizumab (Enspryng), an interleukin-6 receptor (IL-6R) inhibitor, for the treatment of adults with thyroid eye disease (TED).¹ According to Roche, Enspryng is the first and only at-home subcutaneous treatment option for the condition, and it can be administered by a patient or caregiver after training from a health care provider.¹

The FDA reviewed the application under priority review. TED is the second indication for Enspryng, which was first approved in 2020 for neuromyelitis optica spectrum disorder (NMOSD).¹

What is thyroid eye disease?

TED, also known as Graves’ ophthalmopathy, is an inflammatory autoimmune disease affecting the eyes and surrounding tissue. Symptoms include redness and swelling, eyelid retraction, bulging of the eyes (proptosis), double vision (diplopia), and pain, and the disease can be sight-threatening and disfiguring.¹ Roche estimates that TED affects approximately 155 of every 100,000 people in the US.¹

How does satralizumab work?

Satralizumab is a humanized monoclonal antibody that binds both soluble and membrane-bound IL-6R, inhibiting IL-6-mediated signaling.¹ It incorporates Chugai’s antibody recycling technology, which enables pH-dependent binding to IL-6R and repeated engagement of the target, extending the antibody’s time in circulation.¹

The rationale for targeting this pathway in TED is described in the published design of the phase 3 program. “Molecular and clinical evidence suggest that IL-6 and its receptor (IL-6R) play a key role in the pathogenesis of TED,” the investigators wrote, adding that “elevated IL-6 expression correlates with orbital tissue expansion and drives fibrosis development.”²

What did the SatraGO trials show?

SatraGO-1 and SatraGO-2 were identically designed, randomized, placebo-controlled phase 3 trials that enrolled 131 and 127 patients, respectively.² Patients received subcutaneous satralizumab or placebo at Weeks 0, 2, and 4, then every four weeks through Week 20.³ The primary endpoint was the proportion of patients with active, moderate-to-severe TED achieving at least a 2-mm reduction in proptosis in the study eye at Week 24.²

The two trials produced different results. In the active TED population of SatraGO-2, 52.9% of patients receiving satralizumab achieved a proptosis response, compared with 23.4% of those receiving placebo, and 60.7% achieved diplopia reduction, compared with 25.8%.¹ SatraGO-1 did not meet its primary endpoint at Week 24.¹ In that trial, proptosis response rates were 49% for satralizumab and 31% for placebo (P = .0715).³

No new safety signals were identified, and the safety profile was consistent with the drug’s known profile in NMOSD.¹ Week 24 results from both trials have been published in Ophthalmology.⁴

“As a clinical trial investigator, I have seen firsthand the potential of targeted therapies such as Enspryng,” said César A. Briceño, MD, associate professor of ophthalmology at the Scheie Eye Institute, University of Pennsylvania. “The availability of an effective subcutaneous treatment option could provide greater flexibility for both patients and physicians while reducing the logistical burden associated with infusion-based therapies.”¹

How does Enspryng fit into TED treatment?

The first FDA-approved TED therapy, teprotumumab (Tepezza), an insulin-like growth factor-1 receptor (IGF-1R) inhibitor, was approved in January 2020 and is given as 8 intravenous infusions, once every 3 weeks.⁵ Enspryng is dosed subcutaneously every four weeks during its maintenance phase.¹

The appeal of moving biologics from intravenous to subcutaneous delivery has come up in previous BioPharm International® coverage. In an interview, Charles Theuer, MD, PhD, chief medical officer at Halozyme, described the time savings. “You decrease the administration time, literally from hours to minutes and sometimes as little as seconds,” Theuer said.

Roche is also developing Enspryng in other autoimmune and inflammatory diseases. The FDA granted priority review to a supplemental Biologics License Application for myelin oligodendrocyte glycoprotein antibody-associated disease in September 2026, with a decision expected in January 2027.¹

References

1. Roche. FDA approves Roche’s Enspryng, a first-in-class IL-6R inhibitor, as the first and only at-home subcutaneous treatment option for thyroid eye disease (TED). Press release. Published October 16, 2026. Accessed October 16, 2026.
2. Ezra D, Collins A, Haskova Z, et al. Targeting IL-6 receptor signaling with satralizumab in thyroid eye disease: design of the Phase 3 SatraGO-1 and SatraGO-2 trials. Ophthalmol Ther. 2025;14(12):3119-3132. Published online October 9, 2025.
3. Ortiz-Perez S, Briceño C, Idowu O, et al. Primary results of the Phase 3 SatraGO-1 and SatraGO-2 trials: efficacy and safety of satralizumab in thyroid eye disease. Abstract presented at: European Society of Ophthalmic Plastic and Reconstructive Surgery (ESOPRS) 2026 meeting. Accessed October 16, 2026.
4. Briceño CA, Idowu OO, Khong JJ et al. Efficacy and safety of satralizumab for thyroid eye disease: Week 24 results from the Phase III SatraGO-1 and SatraGO-2 randomized trials. Ophthalmology. 2026. doi: 10.1016/j.ophtha.2026.08.039
5. Inserro A. FDA approves biologic teprotumumab, first drug for thyroid eye disease. AJMC. Published January 21, 2020. Accessed October 16, 2026.