Fruquintinib plus camrelizumab combined with paclitaxel liposome and nedaplatin as first-line treatment for advanced esophageal squamous cell carcinoma (ESCC): A single-arm, phase II clinical trial.

445 Background: Camrelizumab in combination with chemotherapy has become a standard of care for the first-line treatment of advanced ESCC. Previous studies have indicated synergistic effect of fruquintinib in combination with chemotherapy or immunotherapy. Hence, we conducted a phase II trial to evaluate the efficacy and safety of fruquintinib plus camrelizumab, paclitaxel liposome, and nedaplatin as a first-line therapy for advanced ESCC. Methods: This is a single-arm, phase II study consisting of a dose-finding and a dose-expansion phase. A total of 33~36 patients aged 18~80 years with previously untreated advanced ESCC and an ECOG PS of 0-2 were planned to be enrolled. The dose-finding phase followed a 3+3 approach in order to determine the recommended phase II dose (RP2D) of fruquintinib for dose expansion. Patients received fruquintinib (3 mg, 4 mg, and 5 mg once daily on days 1-14, starting at 4 mg) orally, plus intravenous camrelizumab 200 mg d1, paclitaxel liposome 135 mg/m 2 d1, and nedaplatin 70 mg/m 2 d1, 21 days as one cycle. A maximum of 6 cycles was conducted, followed by maintenance therapy with fruquintinib in combination with camrelizumab. The primary endpoint was objective response rate (ORR, RECIST 1.1). Secondary endpoints included RP2D, disease control rate (DCR), progression-free survival (PFS), and adverse events (AEs). Results: As of August 24, 2024, 11 patients (9 males) were enrolled with a median age of 66 years (range 50-76). All patients had distant metastases, and the median number of sites of metastasis was 2 (range 1-5). In the dose-finding phase, 3 patients were treated with 4 mg of fruquintinib, and 6 patients were treated with 5 mg of fruquintinib. No dose-limiting toxicities (DLTs) were observed. Thus, the RP2D of fruquintinib was established as 5 mg once daily on days 1-14, 21 days as one cycle. Of the 7 evaluable patients, 6 achieved partial response, and 1 had stable disease. The ORR was 85.7% (95% CI 42.1%-99.6%), and the DCR was 100.0% (95% CI: 59.0%-100.0%). The median PFS was not reached. The most common treatment-related adverse events (TRAEs) were anemia (7/11), hypercholesterolemia (6/11), hypoalbuminemia (5/11), oral mucositis (5/11), hematuria (4/11), hypertension (4/11), fatigue (4/11), constipation (3/11), and neutropenia (3/11). Grade 3 TRAEs were identified in 2 patients, including oral mucositis (2/11), and anemia (1/11). No treatment-related serious adverse events (SAEs) or deaths occurred. Conclusions: The combination of fruquintinib, camrelizumab, paclitaxel liposome, and nedaplatin demonstrated significant efficacy and manageable toxicity profiles as a first-line treatment for advanced ESCC, suggesting a potential new treatment strategy. Clinical trial information: NCT06010212 .