Linsitinib is Sling Therapeutics' oral IGF-1R inhibitor in Phase 3 development for thyroid eye disease.
Linsitinib is Sling Therapeutics' lead pipeline program, an oral small-molecule inhibitor of insulin-like growth factor 1 receptor (IGF-1R) being developed for thyroid eye disease. It is the first and only oral IGF-1R inhibitor in Phase 3 development for the condition, evaluated in the pivotal ORBIT trial of approximately 130 adults with moderate to severe active disease. Linsitinib is not approved as a marketed product.
In the completed Phase 2b/3 LIDS trial, the 150 mg twice-daily dose met the primary endpoint of proptosis reduction with statistical significance and reported no drug-related hearing impairment. The program holds U.S. Fast Track designation, and Sling Therapeutics is funding Phase 3 development with the proceeds of a $123 million Series C financing closed in September 2026.