Biotechnology company Tyra Biosciences Inc (Nasdaq: TYRA) reported on Wednesday that its initial Phase 2 SURF302 results for oral dabogratinib in patients with FGFR3-altered low-grade intermediate-risk non-muscle invasive bladder cancer (LG IR NMIBC) identifies 60 mg once daily as the potential dose for its planned registrational adjuvant strategy.

The company said the treatment demonstrated a favourable safety profile, with no clinically significant hyperphosphatemia, nail or ocular toxicity and treatment-related Grade 3 adverse events occurring in 4.5% of participants across the 50 mg and 60 mg cohorts, with none reported at 60 mg.

Among 14 evaluable patients receiving 60 mg, the overall response rate (ORR) was 79% and the best overall complete response (CR) rate was 64% across single and multiple marker lesions. In the single marker lesion group, the 60 mg cohort recorded a 100% ORR and a 75% best overall CR rate. All five patients with 3-month CRs who had reached the 6-month assessment remained in response, while the first study participant remained in CR at 12 months and continued treatment at 14 months.

Preliminary exposure-response analysis showed an 86% ORR among patients above the target steady-state exposure threshold compared with 58% below it.

Tyra Biosciences plans to complete enrolment in the 60 mg cohort and initiate a 70 mg cohort to evaluate dabogratinib in the ablative setting, while engaging health authorities on its Phase 3 design and dose selection.

Separately, the first patient treated in the Phase 2 SURF303 study in low-grade upper tract urothelial cancer achieved a 3-month CR with 60 mg once daily and reported no treatment-emergent adverse events as of 31 August 2026.