Study to Assess Linsitinib in Participants With Moderate to Severe Active Thyroid Eye Disease (TED)

NCT07753603 | Recruiting Phase 3 DMC FDA Drug

• 1 other identifier: SLG-TED-303
• Study Type: interventional
• Target: 130
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate the efficacy, safety, and tolerability of linsitinib in participants with moderate to severe Thyroid Eye Disease (TED).

Conditions

Thyroid Eye Disease, TED; Graves Orbitopathy

Keywords

Thyroid Eye Disease; TED; Graves Orbitopathy; Graves' Disease; Hashimoto's thyroiditis

Outcome Measures

Primary Outcomes (1)

• Measure percentage of participants who are Proptosis Responders at Week 24

  The proptosis responder rate is the percentage of participants with a ≥ 2 mm reduction of proptosis from Baseline in the primary study eye without deterioration (≥ 2 mm increase) of proptosis in the contralateral non-study eye.

  24 weeks

Secondary Outcomes (4)

• Mean change from Baseline in Proptosis to Week 24

  24 Weeks

• Evaluate the effect of linsitinib 150 mg twice daily versus placebo on the overall responder rate at Week 24

  24 Weeks

• Evaluate the effect of linsitinib 150 mg twice daily versus placebo on the mean change from Baseline to Week 24 in the GO-QoL questionnaire overall score.

  24 Weeks

• Evaluate the effect of linsitinib 150 mg twice daily versus placebo on the percentage of participants with a CAS value of 0 or 1 at Week 24 in the primary study eye.

  24 Weeks

Other Outcomes (1)

• To assess the safety and tolerability of linsitinib 150 mg twice daily as compared to placebo over a 24-week period.

  24 Weeks

Study Arms (3)

Double-mask Treatment Arm

EXPERIMENTAL

Participants receive linsitinib 150 mg twice daily for 24 weeks.

Drug: linsitinib

Double-mask Placebo Arm

PLACEBO COMPARATOR

Participants receive placebo 0 mg twice daily for 24 weeks.

Drug: Placebo

Open-label Extension Treatment Arm

EXPERIMENTAL

Proptosis non-responders/relapsed proptosis responders receive linsitinib 150 mg twice daily for 24 weeks.

Drug: linsitinib

Interventions

linsitinib DRUG

150 mg linsitinib is taken twice daily by mouth for 24 weeks

Double-mask Treatment Arm; Open-label Extension Treatment Arm

Placebo DRUG

0 mg placebo taken twice daily by mouth for 24 weeks

Double-mask Placebo Arm

Eligibility Criteria

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

You may qualify if:

• Participants must be ≥ 18 years of age at Screening
• Clinical diagnosis of Graves' Disease and/or autoimmune Hashimoto's thyroiditis associated with active moderate to severe TED with a CAS ≥ 3 (on the 7-item scale) for the most severely affected eye (primary study eye) at Screening and Baseline.
• Moderate to severe active TED (not sight-threatening but has an appreciable impact on daily life), with diagnosis of TED within 15 months prior to the Screening visit and usually associated with 1 or more of the following: lid retraction ≥ 2 mm, moderate or severe soft tissue involvement, proptosis ≥ 3 mm above normal for race and gender, and/or inconstant or constant diplopia.
• Participants must be euthyroid with the participant's baseline disease under control or have mild hypo- or hyperthyroidism (defined as free thyroxine \[FT4\] and free triiodothyronine levels \[FT3\] \< 50% above or below the normal limits of the central laboratory) at Screening.
• Does not require immediate ophthalmic surgery, radiotherapy to orbits or other ophthalmological intervention at the time of Screening and is not planning for any such treatment during the course of the study.

You may not qualify if:

• Any progressing optic neuropathy due to TED that has worsened in the last 6 months in the opinion of the investigator.
• Corneal decompensation unresponsive to medical management.
• Previous orbital irradiation or orbital surgery in either eye.
• Any glucocorticoid use (IV or oral) with a cumulative dose equivalent to ≥ 1 g of methylprednisolone or equivalent for the treatment of TED within 8 weeks of Screening.
• Prior IGF-1R inhibitor therapy for any condition.

Sponsors & Collaborators

• Sling Therapeutics, Inc.: lead

Study Sites (1)

Advancing Research International

Las Vegas, Nevada, 89144, United States

RECRUITING

MeSH Terms

Conditions

Graves Ophthalmopathy; Graves Disease; Hashimoto Disease

Interventions

3-(8-amino-1-(2-phenylquinolin-7-yl)imidazo(1,5-a)pyrazin-3-yl)-1-methylcyclobutanol

Condition Hierarchy (Ancestors)

Eye Diseases, Hereditary; Eye Diseases; 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; Thyroiditis, Autoimmune; Thyroiditis

Central Study Contacts

Cathy Radovich

CONTACT

(734) 223-1786; cathy.radovich@slingtx.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: August 3, 2026
• First Posted: August 7, 2026
• Study Start: August 4, 2026
• Primary Completion (Estimated): June 30, 2028
• Study Completion (Estimated): June 28, 2030
• Last Updated: August 11, 2026

Record last verified: 2026-08

Locations

US (1)