Tyra Biosciences shares fell 21.6% to $20.95 after initial Phase 2 SURF302 results for oral dabogratinib in FGFR3-altered, low-grade, intermediate-risk non-muscle invasive bladder cancer. Among 26 evaluable patients, the overall response rate was 86% for those reaching target exposure and 58% for those below it. Complete response was 57% at 60mg once daily, compared with 50% in the pooled 50mg and 60mg groups, below earlier analyst expectations of a 70%-80% rate. Tyra identified 60mg as the dose for planned registrational studies, plans to complete enrollment at that dose and begin a 70mg tumor-ablation cohort, and will consult health authorities on Phase 3 design and dosing. Initial SURF303 observations in upper tract urothelial cancer showed a complete response after three months in the first patient treated with 60mg, with zero adverse events.