FDA Approves Enspryng as At-Home Subcutaneous Treatment for Thyroid Eye Disease

The FDA has approved satralizumab-mwge (Enspryng, Genentech) for the treatment of adults with thyroid eye disease (TED), Genentech announced. The company described the interleukin-6 receptor (IL-6R) inhibitor as the first and only at-home subcutaneous treatment option for TED.

Satralizumab is a humanized monoclonal antibody, developed by Chugai, a member of the Roche Group. It binds both soluble and membrane-bound IL-6Rs to inhibit IL-6–mediated signaling. According to Genentech, patients or caregivers can administer it after training from a health care provider, with dosing every 4 weeks during the maintenance phase. The TED approval followed a priority review designation. It is the drug’s second indication, after neuromyelitis optica spectrum disorder (NMOSD) in 2020.

The approval was based on the phase 3 SatraGO-1 and SatraGO-2 trials. These identically designed, randomized, placebo-controlled studies enrolled 258 adults with active, moderate-to-severe TED or chronic TED from 19 countries. The primary endpoint was the proportion of patients with active, moderate-to-severe TED who achieved at least a 2mm reduction in proptosis in the study eye at week 24.

SatraGO-1 did not meet its primary endpoint. In the active TED population of SatraGO-2, a proptosis response occurred in 52.9% of patients receiving satralizumab and 23.4% of those receiving placebo. Diplopia reduction occurred in 60.7% and 25.8%, respectively. Genentech said results were consistent in the overall SatraGO-2 population, which included patients with chronic TED. According to the company, no new safety signals were identified, and the safety profile was consistent with satralizumab’s known profile in NMOSD.

Genentech’s safety information lists contraindications in patients with active hepatitis B infection or active or untreated latent tuberculosis. It also lists risks of serious infections, increased liver enzymes, decreased neutrophil counts, and serious allergic reactions. Separately, the FDA granted priority review in September 2026 to a supplemental biologics license application for satralizumab in myelin oligodendrocyte glycoprotein antibody-associated disease, with a decision expected in January 2027.

Source: Genentech. FDA approves Genentech’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. Genentech; October 15, 2026. Accessed October 19, 2026.