Amgen (NASDAQ: AMGN) today announced TEPEZZA^® (JAN: Teprotumumab (Genetical Recombination)) has been approved for the treatment of active or high clinical activity score (CAS) Thyroid Eye Disease (TED) by Japan's Ministry of Health, Labour and Welfare (MHLW).

TED is a serious, progressive and potentially vision-threatening rare autoimmune disease that can cause proptosis (eye bulging), diplopia (double vision), eye pain, redness and swelling.¹ There are approximately 25,000 - 35,000 people living with TED in Japan, inclusive of both active and chronic (low CAS) TED.² TEPEZZA is now the first and only medicine approved in Japan to treat active TED. A separate trial to study the efficacy of TEPEZZA in chronic TED patients in Japan is currently ongoing.

"This is the first approval for TEPEZZA in Asia and marks a significant milestone for the global treatment of TED," said Jay Bradner, M.D., executive vice president, Research and Development, and chief scientific officer at Amgen. "Historically, patients with TED have been managed with complex surgeries and high-dose steroids, which can cause further complications. With TEPEZZA, doctors have a nonsurgical and nonsteroidal option that treats a root cause of this debilitating disease."

TEPEZZA received orphan drug designation in Japan, which provided a nine-month regulatory review period compared to the standard 12-month review. The approval was based on the positive results of OPTIC-J (jRCT2031210453), a Phase 3 randomized, double-masked, placebo-controlled, parallel-group, multicenter study evaluating the efficacy, tolerability and safety of TEPEZZA in the treatment of patients with active TED in Japan.

The primary endpoint in the trial was met, as 89% of patients treated with TEPEZZA had a clinically meaningful improvement in proptosis (≥2 mm) compared with placebo (11%; p<0.0001) at week 24. The safety profile was consistent with the complete body of clinical data supporting TEPEZZA.³ A second Phase 3 clinical trial is ongoing in Japan evaluating TEPEZZA among adults with chronic TED and a low CAS (jRCT2031220730).

"People living with active TED can experience a significant burden of disease with symptoms that can make daily life difficult to navigate," said Yuji Hiromatsu, M.D., a professor emeritus at the Kurume University Medical Center and physician at the Diabetes, Thyroid and Endocrine Center at the Shin-Koga Hospital. "The approval of TEPEZZA in Japan is an important advancement for patients and offers a new treatment option that targets the underlying mechanism of the disease."

In addition to Japan, TEPEZZA is currently approved in the United States, Brazil and the Kingdom of Saudi Arabia, and is under regulatory review in Europe, Canada and Australia.