PR Newswire·Sep 9, 2026, 7:00 AM ET

Tyra Biosciences Reports Initial Phase 2 SURF302 Results Supporting the First Potential Oral Innovation in LG IR NMIBC with Dabogratinib

TYRA

Tyra Biosciences announced initial results from the Phase 2 SURF302 study of oral dabogratinib for FGFR3-altered low-grade intermediate-risk non-muscle invasive bladder cancer (LG IR NMIBC).
The 60 mg once-daily dose was identified as the potential regimen for the planned registrational adjuvant development strategy.
In the 60 mg QD cohort of combined single & multiple marker lesion patients (n=14), the overall response rate was 79% with a 64% best overall response complete response rate.
In the 60 mg QD cohort of single marker lesion patients (n=8), the overall response rate was 100% with a 75% best overall response complete response rate.
Safety data showed no clinically significant hyperphosphatemia, nail toxicity, or ocular toxicity, with low frequency transaminase treatment-emergent adverse events (<10%).
Grade 3 treatment-related adverse events occurred in fewer than 5% of patients, with none reported at the 60 mg QD dose.
No dose reductions or treatment-related discontinuations were observed in the 60 mg QD cohort.
Preliminary exposure-response analyses suggest higher drug exposure may be beneficial for patients with multiple marker lesions, supporting the evaluation of a 70 mg dose in an ablative setting.
Tyra plans to complete enrollment in the 60 mg QD cohort & initiate a 70 mg QD cohort to explore dabogratinib in the ablative setting.
In the Phase 2 SURF303 study for low-grade upper tract urothelial cancer (LG UTUC), the first patient treated achieved a complete response at 3 months with 60 mg QD.
Tyra intends to engage health authorities regarding Phase 3 study design & dose selection before preparing for a registrational adjuvant study.