Amgen Reports Successful Phase 3 Results for TEPEZZA Subcutaneous Delivery in Thyroid Eye Disease

Amgen has announced a major clinical breakthrough with positive topline results from its Phase 3 trial of TEPEZZA (teprotumumab-trbw) administered via a subcutaneous on-body injector (OBI). The study confirms that this new delivery method offers comparable efficacy to the traditional intravenous (IV) version, potentially transforming the treatment landscape for patients with moderate-to-severe active Thyroid Eye Disease (TED).

Key Clinical Outcomes

The trial achieved its primary endpoint with high statistical significance, demonstrating the potency of the subcutaneous approach:

Response Rate: 77% of participants receiving the OBI treatment achieved a significant proptosis (eye bulging) response, compared to 19.6% in the placebo group.
Physical Improvement: Patients saw a mean proptosis reduction of 3.17 mm.
Comprehensive Relief: The study also reported significant improvements in double vision (diplopia) and overall quality of life scores.

Patient Convenience and Safety

The shift from clinic-based IV infusions to a “wearable” on-body injector represents a leap forward in patient-centric care.

Administration: Delivered every two weeks for a 12-injection course.
Consistency: The safety profile remained consistent with the known effects of TEPEZZA IV, with muscle spasms and tinnitus being the most common side effects. Injection site reactions were mild and did not result in any treatment discontinuations.

The Future of TED Treatment

As the only FDA-approved medicine for TED, TEPEZZA has already reached over 25,000 patients. This new subcutaneous option aims to make therapy more accessible, reducing the burden of infusion center visits while maintaining “best-in-class” efficacy.