First Tracks Biotherapeutics is a clinical-stage biotech company developing therapeutic antibodies for autoimmune and inflammatory diseases. The company was spun out of AnaptysBio in April 2026, taking the drug development pipeline while AnaptysBio retained royalty-generating assets. First Tracks trades on Nasdaq under "TRAX" and has no approved products or product revenue. The company funds operations through equity financing, entering independence with roughly $175M in pro forma cash following a concurrent private placement at spin-off. Its pipeline has three wholly owned clinical-stage antibodies. Rosnilimab, the lead program, is a PD-1-targeting antibody designed to selectively deplete disease-causing T cells while sparing regulatory T cells. A Phase 2b trial in moderate-to-severe rheumatoid arthritis hit its primary endpoint, and the company is assessing Phase 3 advancement. ANB033 is a CD122 antagonist blocking IL-15 and IL-2 signaling, currently in Phase 1b trials for celiac disease and eosinophilic esophagitis — two indications with significant unmet need. ANB101, in-licensed from Centessa, targets plasmacytoid dendritic cells to suppress type I interferon secretion, with potential applicability in lupus; a Phase 1a trial in healthy volunteers is ongoing. First Tracks relies entirely on contract manufacturers for clinical supply. The eventual path to revenue would be through approved product sales or licensing and partnership arrangements with larger pharmaceutical companies, none of which exist today. A rosnilimab Phase 3 program would likely require additional fundraising or a partnership.