TOPLINE

In an analysis of two phase 3 trials, satralizumab was associated with a greater reduction in bulging of the eyes than placebo among patients with active thyroid eye disease (TED) and reached statistical significance in one of the studies.

METHODOLOGY

• Researchers reported 24-week findings from two ongoing phase 3 clinical trials (SatraGO-1 and SatraGO-2) investigating the efficacy and safety of satralizumab in patients with TED over a planned duration of 72 weeks.
• They included adults with active, moderate-to-severe TED or inactive TED at 85 sites worldwide between October 2023 and January 2025. SatraGO-1 included 131 patients, and SatraGO-2 included 127 patients; across the 2 trials, the mean age was about 50 years, and women made up 60.3%-77.9% of participants.
• Patients were randomly assigned to receive either subcutaneous satralizumab or placebo every 4 weeks through week 20, after receiving loading doses at weeks 0, 2, and 4.
• The primary endpoint at week 24 was the proportion of patients with active TED whose eye bulging (proptosis) reduced by at least 2 mm from baseline, without a corresponding worsening of at least 2 mm in the fellow eye.
• Secondary endpoints included reduction of inflammation (using the clinical activity score) and reduction of double vision (using the Gorman scale). Safety was also assessed.

TAKEAWAY

• In SatraGO-2, 52.9% of patients in the satralizumab group achieved the primary endpoint compared with 23.4% in the placebo group (treatment difference, 28.9%; P = .0011). In SatraGO-1, the difference did not reach statistical significance.
• More patients who received satralizumab than those who received placebo had a reduction of at least 2 points in clinical activity score in both the SatraGO-1 (78.0% vs 54.9%; P = .0120) and SatraGO-2 (89.6% vs 63.3%; P = .0009) trials.
• In SatraGO-2, a higher proportion of patients who received satralizumab vs placebo experienced improvement in double vision (P = .0044).
• Through week 24, rates of serious adverse events and discontinuation of treatment were low in both arms; no serious infections occurred in the satralizumab arms. No fatal adverse events were reported.

IN PRACTICE

"Given the key role of IL-6 [interleukin-6] in TED pathogenesis, and the limitations of currently approved and off-label treatment options, IL-6 pathway inhibition with satralizumab may represent a new treatment paradigm for patients with TED," the researchers reported.

SOURCE

The study was led by César A. Briceño, MD, of the University of Pennsylvania in Philadelphia. It was published online on September 7 in Ophthalmology.

LIMITATIONS

Researchers did not include an active control treatment for comparison. They excluded patients with active TED previously treated with systemic corticosteroids, biologics, or immunosuppressants within 3 months of screening. The sample size of patients with inactive TED was small.

DISCLOSURES

The study received funding from F. Hoffmann-La Roche AG. Several authors reported being employees of and holding stocks/stock options in F. Hoffmann-La Roche AG; Genentech, Inc.; and Roche Products Ltd. Multiple authors reported receiving consulting fees, advisory board roles, research support, or speaker fees from various organizations. Detailed author disclosures are reported in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.