FDA Approves Teprotumumab for Thyroid Eye Disease

The US Food and Drug Administration (FDA) has approved teprotumumab (Tepezza) for the treatment of adults with thyroid eye disease, making the Horizon Therapeutics Ireland DAC therapy the first indicated for the rare optical condition.

Teprotumumab, which received unanimous support from the FDA Dermatologic and Ophthalmic Drugs Advisory Committee (DODAC) in a vote last month, is a fully human monoclonal antibody IGF-1R inhibitor used intravenously to treat thyroid eye disease.

The therapy was approved based on the results of a pair of randomized, placebo-controlled studies including 170 patients with active thyroid disease. A majority of patients in the first (71%) and second (83%) treated with teprotumumab demonstrated a >2 mm reduction in proptosis, versus just 20% and 10% of placebo-treated patients in the trials, respectively.

Common adverse reactions observed in treated patients included muscle spasm, nausea, alopecia, diarrhea, fatigue, hyperglycemia, hearing loss, dry skin, dysgeusia, and headache.

Thyroid eye disease is most frequently associated with proptosis, or the outward bulging of the eye, which can cause symptoms including pain, double vision, light sensitivity, or difficulty closing the eye. Its small patient population is made up primarily of women, and its burden could affect everyday activities including driving, reading, and working.

In an interview with HCPLive® while at the American Academy of Ophthalmology (AAO) 2019 Annual Meeting in San Francisco, teprotumumab clinical investigator and director of the Cedars-Sinai Orbit and Thyroid Eye Disease Center, Raymond Douglas, MD, PhD, explained the value of this now-approved regulation of the IGF-1R inhibitor.

“I think that there will be a time where we thought of treating this disease with teprotumumab, and a time after, because this really does apply to the large majority of patients who get thyroid eye disease and are subjected to this really horrible disease process—and it reverses each aspect of the disease,” Douglas said. “So, it really adds up to a dramatic improvement in that patient’s quality of life.”

Wiley Chambers, MD, deputy director of the Division of Transplant and Ophthalmology Products in the FDA's Center for Drug Evaluation and Research, called the teprotumumab approval an important milestone for treatment of the rare disease.

“This treatment has the potential to alter the course of the disease, potentially sparing patients from needing multiple invasive surgeries by providing an alternative, non‑surgical treatment option," Chambers said in a statement. "Additionally, thyroid eye disease is a rare disease that impacts a small percentage of the population, and for a variety of reasons, treatments for rare diseases are often unavailable.”

Teprotumumab was previously granted Priority Review, Fast Track, and Breakthrough Therapy designations by the FDA, and its development was in part supported by the FDA Orphan Products Grants Program.