Safety and Preliminary Anti-Tumor Activity of TYRA-300 in Advanced Urothelial Carcinoma and Other Solid Tumors With FGFR3 Gene Alterations

Inclusion Criteria: Phase 1 Part A and Part B * Men and women 18 years of age or older. * Eastern Cooperative Oncology Group (ECOG) performance status of ≤1. * Histologically confirmed advanced solid tumor who have exhausted standard therapeutic options. * Evaluable (Part A) or measurable (Part B) disease according to RECIST v1.1. * Histologically confirmed advanced solid tumor with an eligible FGFR3 gene mutation or fusion (Part B). Phase 2 * Men and women 18 years of age or older. * ECOG performance status of 0-2 or Karnofsky Performance Scale (KPS) \>70. * At least 1 measurable lesion by RECIST v1.1. * Histologically confirmed locally advanced/metastatic tumor in one of the following categories: * Urothelial carcinoma with an eligible FGFR3 gene mutation or rearrangement who have progressed on a prior FGFR inhibitor and presence of a resistance mutation or other kinase domain mutation. * Urothelial carcinoma with an eligible FGFR3 gene mutation or rearrangement who has not received a prior FGFR inhibitor. * Any solid tumor with an eligible FGFR3 gene mutation or rearrangement. Exclusion Criteria (All Phases): * Has a serum phosphorus level \> upper limit of normal (ULN) during screening that remains \>ULN despite medical management. * Any ocular condition likely to increase the risk of eye toxicity. * History of or current uncontrolled cardiovascular disease. * Active, symptomatic, or untreated brain metastases. * Gastrointestinal disorders that will affect oral administration or absorption of TYRA-300. * Females who are pregnant, breastfeeding, or planning to become pregnant and males who plan to father a child while enrolled in this study.