Pharma powerhouse Amgen has reported that TEPEZZA (teprotumumab-trbw) delivered via a subcutaneous on-body injector (OBI) achieved positive topline results in a Phase 3 trial for patients with moderate-to-severe active Thyroid Eye Disease (TED).
The results show that TEPEZZA OBI matches the efficacy of intravenous (IV) TEPEZZA, which has already treated more than 25,000 patients worldwide.
The trial met its primary endpoint, with a 77% proptosis response rate during the 24-week placebo-controlled period. Key secondary endpoints were also met, including a mean proptosis reduction of -3.17 mm at week 24.
"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," said Jay Bradner, executive vice president of Research and Development at Amgen.
"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 trial also demonstrated significant improvements across multiple secondary endpoints, including overall responder rate, Clinical Activity Score (CAS), diplopia measures, and the Graves' Ophthalmopathy Quality of Life (GO-QoL) appearance subscale.
While not statistically significant, trends favored TEPEZZA OBI in visual functioning scores. Full results are expected to be presented at an upcoming medical congress.
Safety findings aligned with the known profile of IV TEPEZZA. Mild-to-moderate injection site reactions occurred in some patients but did not lead to treatment interruption. The most common adverse events (≥10%) included muscle spasms, tinnitus, weight decrease, ear discomfort, nausea, and diarrhea.
TED is a rare, progressive autoimmune disease that can threaten vision and cause proptosis, diplopia, eye pain, redness, and swelling.
"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," said Dr Madhura A Tamhankar, professor of ophthalmology and neurology at the Scheie Eye Institute, University of Pennsylvania.
"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."
