Amgen has announced positive topline findings from a phase 3 study evaluating a subcutaneous formulation of Tepezza in adults with moderate to severe active thyroid eye disease (TED).
The company said the on‑body injector version delivered efficacy comparable to the intravenous formulation, which is currently the only approved treatment for the condition.
The phase 3 trial met its primary endpoint, with a statistically significant and clinically meaningful proptosis response rate of 76.7 percent at week 24 compared with 19.6 percent for placebo. Mean proptosis reduction reached 3.17 mm, exceeding the threshold regarded as clinically meaningful.
Jay Bradner, executive vice president of Research and Development at Amgen, said: “These results extend and support the best-in-class efficacy of TEPEZZA for people living with Thyroid Eye Disease, now with subcutaneous administration delivering IV-level efficacy.”
He added: “With a well-understood mechanism and established impact in the clinic, we can evolve how the medicine is delivered to potentially reach even more patients through a more convenient subcutaneous option.”
The study also demonstrated statistically significant improvements across several secondary endpoints, including overall responder rate, Clinical Activity Score of 0 or 1, diplopia measures and the Graves’ Ophthalmopathy Quality of Life appearance subscale. A numerical trend favouring Tepezza was observed in the visual functioning subscale, although this did not reach statistical significance.
Safety findings were broadly consistent with the known profile of intravenous Tepezza. Mild to moderate injection site reactions occurred but did not lead to treatment discontinuation. The most common adverse events were muscle spasms, tinnitus, weight decrease, ear discomfort, nausea and diarrhoea.
Dr Madhura A Tamhankar, professor of ophthalmology and neurology at the Scheie Eye Institute, University of Pennsylvania, said: “Thyroid Eye Disease can be a profoundly debilitating condition, affecting not only vision but also daily functioning with symptoms like double vision and eye bulging.”
She added: “Expanding administration options through subcutaneous delivery opens the possibility of a more accessible experience for patients with Thyroid Eye Disease and is critical to serving diverse patient needs. The potential to achieve comparable efficacy to IV makes this advancement compelling.”
