A Phase III Study of KHN939 in Chinese Patients With Moderate-to-Severe Active Thyroid Eye Disease

NCT07720635 | Not Yet Recruiting Phase 3

• 1 other identifier: KHN939-60101
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This is a multicenter, randomized, double-masked, placebo-controlled Phase 3 study to evaluate the efficacy, safety, immunogenicity, and population pharmacokinetic (PopPK) characteristics of KHN939 in Chinese patients with moderate-to-severe active thyroid eye disease (TED). Approximately 60 participants who meet the study eligibility criteria will be randomized in a 2:1 ratio (stratified by smoking status) to receive 8 infusions of KHN939 or placebo q3W.

Conditions

Thyroid Eye Disease

Outcome Measures

Primary Outcomes (1)

• The proptosis responder rate of the study eye

  Defined as percentage of subjects with a ≥ 2mm reduction from Baseline in proptosis in the study eye, without deterioration \[≥ 2 mm increase\] of proptosis in the non-study eye at Week 24. Proptosis assessment: amount of protrusion of the eye from the orbital rim measured by Hertel exophthalmometer.

  Week 24

Secondary Outcomes (11)

• Proptosis responder rate in the study eye

  Week 12

• Overall responder rate in the study eye

  week 12, week 24

• Change from baseline in proptosis measurement of the study eye

  week 12, week 24

• Change in Quality of Life (GO-QoL) Scores

  week 12, week 24

• Change from baseline in Clinical Activity Score (CAS) in the study eye

  week 12, week 24

Other Outcomes (4)

• Change from baseline in ocular motility of the study eye

  week 12, week 24

• The number, incidence, severity, and relevance to study drugs or treatments of all ocular and other systemic AEs, TEAEs, AESIs, and SAEs

  From the Screening period through study completion, with each participant completing all study visits over approximately 28 weeks, comprising a Screening Period (up to 4 weeks), a Treatment Period (21 weeks), and a Safety Follow-up Period (3 weeks).

• Incidence of anti-drug antibodies (ADA) and neutralizing antibodies (NAbs)

  Up to Week 24

Study Arms (2)

KHN939 20 mg/kg

EXPERIMENTAL

8 infusions of KHN939 q3W for a total of 21 weeks

Drug: KHN939

Placebo

PLACEBO COMPARATOR

8 infusions of placebo q3W for a total of 21 weeks

Drug: Placebo

Interventions

KHN939 DRUG

Intravenous (IV) infusion: 20 mg/kg every 3 weeks (Q3W) for a total of 8 doses over 21 weeks

KHN939 20 mg/kg

Placebo DRUG

Intravenous (IV) infusion: placebo every 3 weeks (Q3W) for a total of 8 doses over 21 weeks

Placebo

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18-70 years (inclusive) at the time of signing the informed consent form (ICF), male or female
• Weight between 45 kg and 100 kg
• Diagnosed with moderate-to-severe active TED:
• Proptosis ≥18 mm, accompanied by at least one of the following: (a) eyelid retraction ≥2 mm; (b) moderate to severe soft tissue involvement; (c) intermittent or continuous diplopia
• CAS ≥ 3 points
• Duration of active TED symptoms ≤12 months prior to screening (documented by patient history or medical records)
• Female participants of childbearing potential must have a negative serum pregnancy test during screening and agree to use an effective method of contraception from screening until 90 days after the last dose of the study drug. (Note: Women of non-childbearing potential, defined as surgically sterile or postmenopausal, are exempt.) Male participants must agree to use birth control from screening until at least 90 days after the dose of study drug.
• Able to comply with all protocol-required procedures, examinations, and symptom reporting.

You may not qualify if:

• Known hypersensitivity to any component of the study drug formulation, or prior hypersensitivity to any monoclonal antibodies
• Proptosis at Day 1 (pre-dose) that has decreased by ≥2 mm relative to screening
• CAS at Day 1 (pre-dose) that has decreased by ≥2 points relative to screening
• Ocular conditions:
• Prior or investigator-assessed diagnosis of dysthyroid optic neuropathy (DON) at screening
• Corneal involvement in the study eye without improvement after appropriate treatment
• Prior orbital radiotherapy or surgery for TED in the study eye (including orbital decompression, strabismus correction, eyelid correction)
• Requires immediate or planned ophthalmic surgical intervention during the study period
• Has any pre-existing ocular condition (e.g., high myopia, anticipated cataract surgery) that, as determined by the investigator, would preclude study participation or complicate the interpretation of study results;
• Prior/concomitant treatments:
• Cumulative corticosteroid use for TED ≥1 g methylprednisolone equivalent. \[Note: Participants receiving \<1 g and discontinued ≥30 days prior to screening are eligible\]
• Corticosteroid use within 30 days of screening (except topical, intranasal, inhaled, or intra-articular)
• Periorbital/periocular corticosteroid injection within 90 days of screening
• Corticosteroid or non-steroidal immunosuppressant eye drops within 7 days of screening
• Oral or IV non-steroidal immunosuppressants within 90 days of screening

Sponsors & Collaborators

• Beijing Kanghong Biological Medicine Co., Ltd.: lead

Study Sites (1)

Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University

Shanghai, Shanghai Municipality, 200135, China

Location

MeSH Terms

Conditions

Graves Ophthalmopathy

Condition Hierarchy (Ancestors)

Eye Diseases, Hereditary; Eye Diseases; Graves Disease; Exophthalmos; Orbital Diseases; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Goiter; Thyroid Diseases; Endocrine System Diseases; Hyperthyroidism; Autoimmune Diseases; Immune System Diseases

Central Study Contacts

Zhili Niu

CONTACT

+86-028-87516260; niuzhili@cnkh.com

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 10, 2026
• First Posted: July 22, 2026
• Study Start: August 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): June 1, 2027
• Last Updated: July 23, 2026

Record last verified: 2026-06

Locations

CN (1)