BASEL, Switzerland, June 30, 2026
Roche has announced that the U.S. Food and Drug Administration (FDA) has granted Priority Review to the supplemental Biologics License Application (sBLA) for Enspryng® (satralizumab) as a treatment for thyroid eye disease (TED), bringing the therapy one step closer to becoming the first and only at-home subcutaneous disease-modifying treatment for patients with this debilitating autoimmune condition. The FDA’s acceptance of the application is supported by compelling evidence from the global Phase III SatraGO-1 and SatraGO-2 clinical trials, which demonstrated clinically meaningful improvements in proptosis (bulging eyes), diplopia (double vision), and overall disease activity in adults with moderate-to-severe TED. If approved, Enspryng would introduce an innovative treatment option that combines disease-modifying efficacy, a favorable safety profile, and convenient self-administration at home, addressing a significant unmet need for patients living with a condition that can lead to permanent facial disfigurement and vision-threatening complications. The FDA is expected to issue its decision by October 15, 2026, marking a pivotal milestone in Roche’s expanding autoimmune and ophthalmology portfolio.
Phase III SatraGO Program Demonstrates Strong Clinical Outcomes
The FDA’s Priority Review is based on positive findings from the SatraGO-1 and SatraGO-2 Phase III studies, two randomized, placebo-controlled, multicenter clinical trials that enrolled 258 patients across 19 countries with active, moderate-to-severe thyroid eye disease. The primary endpoint evaluated the proportion of patients achieving at least a 2 mm reduction in proptosis after 24 weeks of treatment. In the SatraGO-2 study, 53% of patients treated with Enspryng achieved significant proptosis reduction compared with 23% receiving placebo, successfully meeting the primary endpoint.
While SatraGO-1 showed 49% of patients achieving a proptosis response compared with 31% in the placebo group, the study also provided important confirmatory evidence supporting the therapy’s clinical benefit. Across both trials, Enspryng significantly improved secondary endpoints, including reductions in Clinical Activity Score (CAS) in up to 90% of patients and improvements in double vision (diplopia) in up to 61% of treated participants. Importantly, the therapy demonstrated a well-established safety profile consistent with previous clinical experience, with no new safety concerns identified during the studies.
First At-Home Disease-Modifying Therapy Could Transform TED Care
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Thyroid eye disease is a chronic autoimmune inflammatory disorder affecting approximately 155 people per 100,000 population, commonly occurring in individuals with thyroid dysfunction and often resulting in eye inflammation, eyelid retraction, proptosis, pain, and double vision. Despite the availability of existing therapies, many patients continue to require more effective, well-tolerated, and convenient treatment options. Enspryng, originally developed by Chugai, a member of the Roche Group, is a humanized monoclonal antibody targeting the interleukin-6 (IL-6) receptor, a key driver of inflammatory activity in autoimmune diseases.
Utilizing innovative recycling antibody technology, the therapy provides sustained inhibition of IL-6 signaling, enabling prolonged suppression of inflammation while supporting convenient subcutaneous self-administration at home. If approved for TED, Enspryng would become the first disease-modifying subcutaneous therapy that patients can administer outside a healthcare facility, potentially transforming long-term disease management while reducing treatment burden for patients and healthcare providers alike.
Priority Review Strengthens Roche’s Autoimmune Innovation Strategy
The FDA Priority Review designation underscores the potential of Enspryng to address a significant unmet medical need while reinforcing Roche’s leadership in developing innovative therapies for autoimmune and inflammatory diseases. Already approved in approximately 90 countries for neuromyelitis optica spectrum disorder (NMOSD) with extensive real-world safety experience in more than 10,000 patients, Enspryng continues to expand into additional indications, including myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and autoimmune encephalitis.
The latest regulatory milestone reflects Roche’s broader strategy of advancing precision biologics that combine scientific innovation with improved patient convenience. Should the FDA approve the application later this year, Enspryng could establish a new standard of care for thyroid eye disease, providing patients with an effective, accessible, and home-based therapeutic option capable of improving both clinical outcomes and quality of life.
Source: Roche press release
