STTK Advances SL-325 to Phase 2b in Crohn's and Phase 2 in HS; Preclinical Data for SL-846

What happened

Shattuck Labs has moved its lead DR3 antagonist SL-325 from pre-IND status into a Phase 2b trial (RECEPTIVE-CD1) in Crohn's disease, with 12-week induction data expected in the first half of 2028. The company also announced plans to initiate a Phase 2 trial (RECEPTIVE-HS1) in hidradenitis suppurativa in the fourth quarter of 2026, expanding the program's reach beyond IBD. Additionally, Shattuck presented preclinical data for SL-846, a second asset, at UEG Week 2026, including chronic toxicology results in non-human primates, signaling pipeline breadth. This marks a significant de-risking step from the previous analysis, which had highlighted SL-325's pre-IND status as a key execution risk, though no human efficacy data has been disclosed yet. The company remains in a competitive TL1A/DR3 field, and investors will likely focus on trial execution and cash runway, given the long timeline to primary data in 2028.

Implication

Investors should view the progression to Phase 2b as a positive signal that SL-325 has cleared early safety hurdles, but the lack of disclosed efficacy data means the investment thesis remains speculative until 2028. The upcoming Phase 2 initiation in HS broadens the potential market opportunity, but adds to clinical and financial execution requirements. Monitoring cash position and any partnership or financing announcements will be critical, as the company will need to fund two ongoing trials over the next 18-24 months. The competitive landscape in TL1A/DR3 remains intense, with large pharmaceutical companies advancing their own assets, so any future data will need to show differentiation. A prudent stance would be to wait for initial biomarker or interim data from the Phase 2b trial, or for a strategic partnership, before adding or initiating positions.

Thesis delta

The prior WAIT rating was driven by SL-325's pre-IND status and high execution risk. With the initiation of Phase 2b and Phase 2 trials, the company has cleared key regulatory milestones, shifting the risk profile from execution/regulatory to clinical efficacy and financing. This supports an upgrade to a SPECULATIVE BUY for risk-tolerant investors, though the long data timeline and undisclosed cash runway warrant continued monitoring.