Innovent Announces Phase 3 RESTORE-3 Study of SYCUME® (Teprotumumab N01 Injection) Met Primary Endpoint in Inactive Thyroid Eye Disease

• SYCUME^® Significantly Improved Proptosis (Response Rate 60.4% / LS Mean Change from Baseline -1.88 mm) with Favorable Safety Profile in Participants with Inactive Thyroid Eye Disease(TED)

SAN FRANCISCO and SUZHOU, China, Oct. 8, 2026 /PRNewswire/ -- Innovent Biologics, Inc. ("Innovent") (HKEX: 01801), a world-class biopharmaceutical company that develops, manufactures and commercializes high-quality medicines for the treatment of oncologic, autoimmune, cardiovascular and metabolic, ophthalmologic and other major diseases, announced today that its independently developed recombinant anti-insulin-like growth factor 1 receptor (IGF-1R) antibody, SYCUME^® (Teprotumumab N01 Injection, R&D code: IBI311), has achieved its primary study endpoint at Week 24 in a multicenter, randomized, double-blind, placebo-controlled Phase 3 clinical study (RESTORE-3) in Chinese participants with inactive thyroid eye disease (TED). In this study, SYCUME^® demonstrated remarkable efficacy in reducing proptosis in participants with inactive TED, with a favorable safety profile.

SYCUME^® is the first IGF-1R antibody drug in China and the second one approved worldwide, filling a 70-year treatment gap in the domestic TED field. Officially included in China's National Reimbursement Drug List on January 1, 2026, SYCUME^® substantially alleviates the financial burden on patients compared to the high cost of overseas counterparts, significantly enhancing drug accessibility. Patients with inactive TED account for approximately two-thirds of the overall TED population¹. Thus, the positive Phase 3 clinical trial results in inactive TED participants mark another milestone breakthrough for SYCUME^® in full-course disease management and precision therapy for TED, providing novel clinical evidence for the treatment of inactive TED in China.

RESTORE-3 is a multicenter, randomized, double-blind, placebo-controlled Phase 3 clinical trial designed to evaluate the efficacy and safety of IBI311 in Chinese participants with inactive TED. A total of 116 eligible participants were randomized in an approximate 2:1 ratio to receive either IBI311 or placebo. The primary efficacy endpoint was the proptosis response rate of the study eye at Week 24, and the key secondary endpoint was the change from baseline in proptosis of the study eye at Week 24.

The study enrolled 116 participants with inactive TED (bilateral CAS ≤ 2 points), with a mean disease duration of 4.3 years, a baseline mean proptosis distance of 22.16 mm in the study eye, and approximately 74.1% of patients presenting with a baseline CAS of 0 or 1 point. Within this baseline population, IBI311 demonstrated clinically meaningful efficacy, successfully achieving all primary and key secondary endpoints:

• Primary Endpoint Achieved: At Week 24, the proptosis response rate in the study eye was significantly higher in the IBI311 group compared with the placebo group (60.4% vs. 23.5%; treatment difference: 36.9 percentage points; p = 0.0003).
• Key Secondary Endpoint Achieved: At Week 24, the least squares mean (LS Mean) change from baseline in study eye proptosis distance in the IBI311 group was -1.88 mm, demonstrating statistically significant superiority over placebo (-0.88 mm; treatment difference: -1.00 mm; p < 0.0001).
• Multidimensional Secondary Benefits: At Week 24, the proptosis response rate in non-study eyes was higher in the IBI311 group than in the placebo group (46.0% vs. 19.8%; p = 0.0071). The LS Mean change from baseline in proptosis distance in non-study eyes reached -1.77 mm in the IBI311 group versus -0.91 mm in the placebo group (p < 0.0001), consistent with the trend observed in study eyes.
• Favorable Safety Profile: During the double-blind treatment and follow-up period, IBI311 exhibited good safety and tolerability. Most treatment-emergent adverse events were mild to moderate in severity, and no new safety signals were identified.

The follow-up of this study is still ongoing, and the complete data will be published in future academic conferences or peer-reviewed academic journals. Although the baseline mean proptosis in RESTORE-3 was lower than that in the TEPEZZA^® study (indirect comparison), the proptosis response rate and the proptosis reduction of IBI311 were generally consistent with TEPEZZA^®'s data² in inactive TED.

Professor Zhongyan Shan from the First Hospital of China Medical University, Lead Principal Investigator of the study stated: "For a long time, effective pharmacological interventions for inactive TED have been lacking. Following the resolution of acute inflammation, patients frequently suffer from persistent proptosis and facial disfigurement. At this stage, surgical intervention has been virtually the sole recourse, leading many patients to forgo treatment and endure the chronic burden of the disease. Results from this trial confirm that SYCUME^® yields robust and clinically meaningful reductions in proptosis even in patients with chronic, inactive TED. This not only validates the therapeutic value of targeting IGF-1R in long-duration inactive TED, but also offers tens of thousands of chronic TED sufferers and clinicians a novel non-surgical treatment paradigm—promising new hope and restored quality of life for patients with inactive TED."

Dr. Lei Qian, Chief R&D Officer (General Biomedicine Pipeline) of Innovent Biologics indicates: "As the first targeted therapy for TED approved and successfully incorporated into the NRDL in China, SYCUME^® has already benefited a vast number of TED patients. With these positive Phase III trial results, SYCUME^® now achieves comprehensive disease coverage ranging from 'early acute control' to 'chronic phase tissue remodeling.' This milestone underscores Innovent's steadfast commitment to serving TED patients while reinforcing SYCUME^®'s leading position in this therapeutic space. We will work closely with medical experts to rapidly translate these clinical findings into standard clinical practice, benefiting a broader patient population and elevating the overall standard of TED diagnosis and care in China."

About Thyroid Eye Disease (TED)

TED, an autoimmune disease involving ocular tissues, is the most common orbital disease in adults. TED affects approximately 25% to 40% of Graves'disease patients, as well as individuals with other thyroid diseases and even those with normal thyroid function³.

The annual incidence of TED is estimated at 16 per 100,000 women and 2.9 per 100,000 men, with a prevalence of 0.1 to 0.3%^4,5. Based on disease severity, TED can be classified into mild, moderate to severe, or sight-threatening. While TED is more common in women, severe cases occur more frequently in men. The exact pathogenesis of TED is not fully understood, but multiple studies suggest that orbital fibroblasts (OFs) in muscle fibers and orbital connective tissue play a key role in orbital soft tissue hyperplasia in TED⁶.

The natural progression of TED is divided into active and inactive stages⁷. Common symptoms include dry eye, foreign body sensation, photophobia, lacrimation, diplopia, and pressure behind the eyes. Typical signs include upper eyelid retraction, proptosis, periorbital soft tissue congestion and edema, and ocular motility disorders. While TED is usually mild to moderate-to-severe, about 3-5% of patients develop sight-threatening TED, which can result in vision-threatening corneal ulcers or compressive optic neuropathy⁸. In addition to affecting appearance and visual function, TED significantly impacts patients' social functioning and quality of life. Historically, inactive TED was deemed non-responsive to medical therapies. Patients with proptosis, strabismus, or eyelid disfigurement affecting aesthetics, visual function, or quality of life typically relied on corrective surgeries, including strabismus surgery, eyelid reconstruction, and orbital decompression⁹. Nevertheless, these surgical procedures are complex, less accessible, and yield only partial clinical improvement, making full restoration to pre-disease status exceptionally difficult to achieve. Recent Chinese and international treatment guidelines and joint consensus have recommended the use of IGF-1R-targeted biologics as a second-line treatment for TED^9-11. Particularly for patients with significant proptosis or diplopia, IGF-1R-targeted biologics can be considered the first-line treatment in such cases¹¹.

About SYCUME^®

SYCUME^® (teprotumumab N01) is a recombinant anti-insulin-like growth factor 1 receptor (IGF-1R) antibody developed by Innovent for the treatment of TED. IGF-1R is a transmembrane tyrosine kinase receptor involved in development, metabolism, and immune regulation, and is overexpressed in Orbital Fibroblasts (OFs), B cells, and T cells of TED patients¹². SYCUME^® blocks the activation of IGF-1R signaling pathway mediated by IGF-1 and related ligands or agonistic antibodies, reducing the expression of downstream inflammatory factors. This inhibition decreases the synthesis of hyaluronic acid and other glycosaminoglycans caused by OFs activation, thereby alleviating inflammation. It also prevents OFs differentiation into adipocytes or myofibroblasts, consequently reducing disease activity and improving clinical manifestations such as proptosis, diplopia, orbital congestion and edema.

In March 2025, SYCUME^® was approved by the NMPA for the treatment of TED. On January 1, 2026, SYCUME^® was officially included in the National Reimbursement Drug List.

About Innovent Biologics

Innovent is a leading biopharmaceutical company founded in 2011 with the mission to empower patients worldwide with affordable, high-quality biopharmaceuticals. The company discovers, develops, manufactures and commercializes innovative medicines that target some of the most intractable diseases. Its pioneering therapies treat cancer, cardiovascular and metabolic, autoimmune and eye diseases.  Innovent has launched 20 products in the market. It has 1 asset under NDA review, 5 assets in phase 3 or pivotal clinical trials, and 19 more molecules in early clinical stage.

Innovent has entered into more than 30 strategic partnerships with global players such as Eli Lilly, Roche, Takeda, Pfizer, Sanofi, Incyte, and MD Anderson Cancer Center, representing an aggregate value of over RMB 350 billion. These efforts have set a benchmark for the high-quality outbound internationalization of China's innovative drug industry.

Guided by the motto, "Start with Integrity, Succeed through Action," Innovent maintains the highest standard of industry practices and works collaboratively to advance the biopharmaceutical industry so that first-rate pharmaceutical drugs can become widely accessible.

For more information, visit www.innoventbio.com, or follow Innovent on Facebook and LinkedIn.

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REFERENCES

1. Schuh A, Ayvaz G, Baldeschi L, et al. Presentation of Graves' orbitopathy within European Group On Graves' Orbitopathy (EUGOGO) centres from 2012 to 2019 (PREGO III). Br J Ophthalmol. 2024 Jan 29;108(2):294-300.
2. Douglas RS, et al. Efficacy and Safety of Teprotumumab in Patients With Thyroid Eye Disease of Long Duration and Low Disease Activity. J Clin Endocrinol Metab. 2023 Dec 21;109(1):25-35.
3. Li Z, Cestari D M, Fortin E. Thyroid eye disease: what is new to know? Curr Opin Ophthalmol. 2018;29(6):528-534.
4. Bartley G. The epidemiological characteristics and clinical course of ophthalmology associated with autoimmune thyroid disease in Olmsted Country, Minnesota. Trans Am Ophthalmol Soc 1994;92:477-588.
5. Hiromatsu Y, Eguchi H, Tani J, Kasaoka M, Teshima Y. Graves' ophthalmopathy: epidemiology and natural history. Intern Med. 2014;53(5):353-60.
6. Ali F, Chorsiya A, Anjum V, Ali A. Teprotumumab (TEPEZZA): from the discovery and development of medicines to USFDA approval for active thyroid eye disease (TED) treatment. Int Ophthalmol. 2021;41(4):1549-1561.
7. Dolman P J. Evaluating Graves' orbitopathy. Best Pract Res Clin Endocrinol Metab.2012;26(3):229-248.
8. Bahn R S. Graves' ophthalmopathy. N Engl J Med. 2010;362(8):726-738.
9. Bartalena L, Kahaly GJ, Baldeschi L, et al. The 2021 European Group on Graves' orbitopathy (EUGOGO) clinical practice guidelines for the medical management of Graves' orbitopathy. Eur J Endocrinol. 2021;185(4):G43-G67.
10. 中华医学会眼科学分会眼整形眼眶病学组, 中华医学会内分泌学分会甲状腺学组. 中国甲状腺相关眼病诊断和治疗指南 （2022年）.中华眼科杂志. 2022;58(9).
11. Burch HB, et al. Management of thyroid eye disease: a Consensus Statement by the American Thyroid Association and the European Thyroid Association. Eur Thyroid J. 2022;11(6):e220189.
12. Douglas RS, Naik V, Hwang CJ, et al. B cells from patients with Graves' disease aberrantly express the IGF-1 receptor: implications for disease pathogenesis. J Immunol 2008;181:5768-5774.

SOURCE Innovent Biologics