OncoMatch/Clinical Trials/NCT05783323
Larotrectinib to Enhance RAI Avidity in Differentiated Thyroid Cancer
Is NCT05783323 recruiting? Yes, currently enrolling (May 2026). This Phase 2 trial studies Larotrectinib monotherapy for differentiated thyroid cancer.
Treatment: Larotrectinib monotherapy — Papillary thyroid cancer (PTC) is the most common form of differentiated thyroid cancer (DTC). The traditional first line treatment for patients with advanced DTC after surgical resection is radioactive iodine (RAI) therapy. However, less than a quarter of patients with lung metastases will achieve a complete response to RAI therapy, and this therapy carries the risk of pulmonary fibrosis and an increasingly recognized risk of secondary malignancies.
Check if I qualifyExtracted eligibility criteria
Cancer type
Thyroid Cancer
Biomarker criteria
Required: NTRK1 fusion
Required: NTRK2 fusion
Required: NTRK3 fusion
Disease stage
Metastatic disease required
Prior therapy
Cannot have received: systemic therapy
Exception: prior 131I is permitted
No prior systemic therapy for thyroid cancer, including tropomyosin receptor kinase (TRK) inhibitors. Note that prior 131I is permitted.
Lab requirements
Blood counts
ANC ≥ 1000/mm3; Platelet count ≥ 100,000/mm3 (transfusion independent, not receiving platelet transfusions for at least 7 days prior to enrollment); Hemoglobin ≥ 8.0 g/dL at baseline (may receive RBC transfusions)
Kidney function
Creatinine clearance or radioisotope GFR ≥ 70 mL/min/1.73 m2 or maximum serum creatinine based on age/gender
Liver function
Bilirubin (sum of conjugated + unconjugated) ≤ 1.5 x ULN for age; SGPT (ALT) ≤ 135 U/L (ULN=45 U/L); serum albumin ≥ 2 g/dL
Adequate Organ Function: Bone Marrow Function: Peripheral absolute neutrophil count (ANC) ≥ 1000/mm3; Platelet count ≥ 100,000/mm3 (transfusion independent, defined as not receiving platelet transfusions for at least 7 days prior to enrollment); Hemoglobin ≥ to 8.0 g/dL at baseline (may receive red blood cell (RBC) transfusions). Adequate Renal Function: Creatinine clearance or radioisotope glomerular filtration rate (GFR) ≥ 70 mL/min/1.73 m2 or a maximum serum creatinine based on age/gender as follows: ... Adequate Liver Function: Bilirubin (sum of conjugated + unconjugated) ≤ 1.5 x upper limit of normal (ULN) for age. Serum glutamic-pyruvic transaminase (SGPT) (ALT) ≤ 135 U/L. For the purpose of this study, the ULN for SGPT is 45 U/L. Serum albumin ≥ 2 g/dL
Structured fields extracted by AI. May contain errors — verify against the official protocol.
US trial sites
- University of California, San Francisco · San Francisco, California
- Children's Hospital of Philadelphia · Philadelphia, Pennsylvania
- St. Jude Children's Research Hospital · Memphis, Tennessee
- MD Anderson Cancer Center · Houston, Texas
- Seattle Children's Hospital · Seattle, Washington
Showing up to 5 US sites. See all sites on ClinicalTrials.gov →
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