Phase II Trial of Tunlametinib in NRAS-Mutant Advanced Thyroid Cancer

This phase II trial evaluates Tunlametinib (MEK inhibitor) ± PD-1 in NRAS-mutant advanced thyroid cancer. Key Objectives: Assess efficacy (ORR by RECIST v1.1) Evaluate safety profiles Study Design: Single-arm, single-center 4 cohorts based on: * Histology (differentiated vs. poorly/undifferentiated) * Prior therapy status Treatment: * Cohorts 1-2: Tunlametinib monotherapy (12mg BID) * Cohorts 3-4: Tunlametinib + PD-1 (commercially available) Key Procedures: Screening: NRAS testing + full staging (CT/MRI/PET) Monitoring: q3-week labs, q9-week imaging Follow-up: 30-day safety visit + q3-month survival tracking Endpoints: Primary: ORR Secondary: Safety (CTCAE), PFS, DoR Unique Aspects: First study targeting NRAS in thyroid cancer with MEK+PD-1 Includes rare aggressive subtypes (poorly/undifferentiated)