Thyroid eye disease has become a test case for what happens after a specialty market proves biologically tractable. Teprotumumab established IGF-1R inhibition and created a meaningful commercial category, but treatment requires intravenous infusions and carries safety and access burdens.
Sling Therapeutics is taking the same pathway into an oral small molecule. Its lead program, linsitinib, is now in the Phase 3 ORBIT study, backed by a $123 million Series C led by Forbion and TPG Life Sciences Innovations. The strategic question is whether an oral therapy can expand the market rather than merely discount an established infusion.
In this deep dive, we are going to look at:
- Why this matters now: TED's shift from niche disease to contested market
- What Sling financed and how ORBIT is designed
- The obvious read versus the deeper signal
- The competitive treatment taxonomy
- The evidence ladder for oral IGF-1R inhibition
- The HealthTech investor's signal
- The strongest clinical counter-thesis
- Four milestones to watch through 2028
- The bottom line for biopharma leaders and investors
