"New Drug Approved for Thyroid Eye Disease, but Early Treatment Is Key to Prognosis"

A Rare Autoimmune Disease Causing Eye Protrusion and Double Vision
Product Approved in Korea This April, but Insurance Coverage Remains a Challenge
Hyunjin Shin of Konkuk University Medical Center: "Access to Treatment for Severe Cases Must Be Improved"

Thyroid eye disease (also known as thyroid-associated ophthalmopathy or thyroid eye disease) is a rare autoimmune disorder in which abnormalities in the immune system cause swelling of the tissues around the eyes, leading to eye protrusion and diplopia (a condition where objects appear double). While it is often misunderstood as merely a cosmetic issue, missing the proper timing for treatment can result in permanent vision impairment. However, in Korea, awareness of the disease remains low and treatment options are limited, causing patients to suffer from prolonged physical and psychological distress.

Professor Shin Hyunjin, an ophthalmologist at Konkuk University Medical Center, is explaining the symptoms and treatments of 'thyroid eye disease' at the Korean Medical Biojournalists Association Media Academy held on the 7th at the RYSE Autograph Collection in Mapo-gu, Seoul. Photo by Jo Inkyung

Hyunjin Shin, Professor of Ophthalmology at Konkuk University Medical Center, pointed out at the "Latest Treatments for Thyroid Eye Disease" media academy hosted by the Korea Medical Bio Journalists Association on July 7 that "Thyroid eye disease must be treated during the active phase to reduce the risk of permanent damage, but access to treatment for patients in Korea is currently very limited."

Thyroid eye disease is caused by immune system abnormalities that trigger inflammation around the eyes and hypertrophy of muscles and fatty tissues. The main symptoms include eye protrusion, eyelid retraction, diplopia, strabismus, eye pain, conjunctival injection, and dry eye. In severe cases, the optic nerve behind the eye can be compressed, potentially leading to permanent vision loss or blindness. Professor Shin explained, "When the eyes protrude, not only does the appearance change, but the eyes may not close completely, resulting in corneal damage. The eye muscles also thicken, causing diplopia, and if the muscles continue to compress the optic nerve, there is a risk of blindness."

Thyroid eye disease often accompanies hyperthyroidism but is an independent disease. It occurs in about 40% of patients with Graves' disease, an autoimmune condition, but can also develop in individuals with normal thyroid function, and in some cases may present before thyroid disease. Therefore, one should not be reassured simply by having normal thyroid function; if eye symptoms appear, a separate ophthalmological exam is necessary.

The disease progresses through an "active" phase characterized by inflammation and an "inactive" phase where tissues become fibrotic. Once the active phase passes and the inactive phase begins, symptoms such as eye protrusion, diplopia, and changes in appearance may become permanent. Professor Shin said, "Patients often report that the disease advances even while receiving treatment, but current therapies do not completely halt progression; they only slow it down. Early and aggressive control of inflammation is essential to minimize long-term damage."

Major Symptoms of Thyroid Eye Disease and Proportion of Patients Experiencing Them

The current standard treatment in Korea is to suppress inflammation during the active phase using steroids and radiation therapy, followed by orbital decompression, strabismus surgery, or eyelid surgery after the disease stabilizes. However, steroids have limited effectiveness in improving eye protrusion and diplopia, and long-term use may cause side effects such as worsening of diabetes and liver damage. Surgery often needs to be performed multiple times and carries risks of complications.

Overseas, "Tepezza" (active ingredient: teprotumumab), a drug targeting the insulin-like growth factor-1 receptor (IGF-1R), the root cause of the disease, was approved by the U.S. Food and Drug Administration (FDA) in 2020 and is now used as a first-line option for patients with moderate to severe active disease. Within three months of administration, reductions in eye protrusion and muscle hypertrophy have been reported, and more recently, its efficacy has also been confirmed in patients with chronic or recurrent disease, leading to expanded indications.

In Korea, Amgen Korea received product approval from the Ministry of Food and Drug Safety in April, and a domestic launch is scheduled for the second half of the year. However, for patients to actually receive prescriptions, institutional and policy support, such as health insurance coverage and designation as a rare disease, is still required. There are an estimated 2,000 patients in Korea with moderate to severe thyroid eye disease.

Thyroid eye disease also has a serious impact on quality of life. According to overseas surveys, 61% of patients experience limitations in everyday activities such as reading, driving, and social participation, while 45% report depression and anxiety. Professor Shin emphasized, "For patients with moderate or severe thyroid eye disease to escape the risks of blindness and depression and return quickly to daily life, the establishment of a systematic disease code is urgently needed." She advised, "The medical community, patient associations, and other stakeholders must work together to promote policy support from the government and to achieve health insurance reimbursement for treatments."

This content was produced with the assistance of AI translation services.