Donafenib as neoadjuvant therapy in locally advanced thyroid cancer: protocol for the DONATHYCA phase II prospective single-arm trial in China.

[INTRODUCTION] The invasion of important structures in locally advanced thyroid cancer (LATC) hinders radical resection, increases the risk of recurrence and even prevents surgery. Creating the opportunity for radical operation in patients with LATC is critical for improving their prognosis. Multitarget tyrosine kinase inhibitors were used as neoadjuvant therapy in several studies. Donafenib produced survival benefits over placebo in Chinese patients with radioiodine-refractory differentiated thyroid cancer in a recent study, but its efficacy in the neoadjuvant setting remains unknown. This study thus aims to assess the efficacy and safety of donafenib as neoadjuvant therapy in LATC.

[METHODS AND ANALYSIS] DONATHYCA is a prospective, exploratory, single-arm phase II study evaluating the efficacy and safety of donafenib as neoadjuvant therapy in patients with LATC. 13 patients will be enrolled. The primary endpoint is the objective response rate as per Response Evaluation Criteria in Solid Tumours V.1.1. The secondary objectives include progression-free survival, the duration of response, the disease control rate, the R0/R1 resection rate, quality of life and toxicity during treatment according to Common Terminology Criteria for Adverse Events V.4.0. Patients will receive donafenib 300 mg two times a day continuously in a 21-day treatment cycle for six cycles.

[ETHICS AND DISSEMINATION] This study was approved by the Ethics Committee of Fujian Cancer Hospital (K2023-144-02) on 27 July 2023 and registered in the China Clinical Trial Registry on 20 September 2023. The results of the study will be presented at academic conferences and published in scientific publications.

[TRIAL REGISTRATION NUMBER] ChiCTR2300075973.