A single-arm, open-label phase II clinical trial of SHR-1210 (camrelizumab) in combination with nimotuzumab in the second-line treatment of advanced esophageal squamous cell carcinoma.

e16007 Background: The prognosis of advanced esophageal cancer is bleak, and the current first-line regimen based on paclitaxel, cisplatin and fluorouracil (TPF) with an effective rate is about 30%. The second-line treatment regimen based on anti-PD-1/PD-L1 monoclonal antibodies obtained median overall survival (mOS) 10.8 months in phase I-II clinical trials, but a large proportion of patients (pts) still do not respond to this therapy. Additionally, nimotuzumab in the previous Cuba phase 2 study had a good disease control rate (DCR) combined with PF regimen. So, we conducted the study to evaluate the new combination modality efficacy and treatment-related adverse events (safety). The primary endpoints was ORR, and the secondary endpoints included overall survival (OS), DCR, progression-free survival (PFS), duration of response (DoR), time to response (TTR), 9-month and 12-month survival rate, as well as safety. Methods: According to the relevant literature, the second-line treatment for ORR is about 15%, and the efficacy of camrelizumab combined with nimotuzumab is expected to be 35%, alpha=0.05. A total of 38 cases were enrolled in the two-stage Simon method, with a bilateral α value of 5% and a test efficiency of 90%. In the first phase, 23 pts were enrolled 15 pts in the second stage. If 9 or more pts reached CR/PR. The trial is considered successful. The dropout rate of 10% was calculated, and a total of 42 pts were enrolled. Results: In this phase 2 study, a total of 41 pts were administered. One case was lost to follow-up. The mean age was 45 years (range, 42-77). The results of the intention-to-treat analysis showed that the ORR was 36% (15/42). The mOS was 12.62 months with median follow-up 8.28 months. The 9-month and 12-month survival rates were 84% and 51%, respectively. The DCR was 81% (34/42). Median PFS was 9.89 months with median follow-up 9.17 months. In terms of safety, the incidence of TEAEs was 60% (25/42), of which 71% (30/42) had adverse events below grade 3 and 26% (11/42) had adverse events above grade 3 including 0 case related to nimotuzumab and 4 cases related to camrelizumab. The overall incidence of adverse drug reactions grade 3 or above was 10% (4/42), of which 0 case related to nimotuzumab and 4 cases related to camralizumab. Conclusions: The combination of camrelizumab and nimotuzumab in the second-line treatment of advanced esophageal squamous cell carcinoma showed a trend benefit for ORR and OS with a controllable toxicity.