Background: CAP 02 study (NCT03736863) is a single-arm phase 2 study to evaluate the efficacy and safety of camrelizumab plus apatinib (a VEGFR2 inhibitor) as second-line treatment in patients with advanced esophageal squamous cell carcinoma (ESCC). Cohort 1 has been published recently, which enrolled patients who progressed after or were intolerant to first-line chemotherapy. The results showed an encouraging median overall survival (OS) of 15.8 months. Here, we reported the preliminary results of cohort 2. Methods: Cohort 2 enrolled unresectable locally advanced, locally recurrent, or metastatic ESCC patients aged 18-75 years with ECOG performance status of 0-1 who had progression on or were intolerant to first-line immunochemotherapy. The disease should be controlled without progression for at least three months during the first-line treatment. Patients received camrelizumab (200 mg Q2W) and apatinib (250 mg QD) until disease progression, intolerable toxicity, or withdrawal for other reasons. The primary endpoint was the objective response rate (ORR). Secondary endpoints included disease control rate, progression-free survival (PFS), duration of response, time to response, OS, 3/6-month PFS rates, 6/9/12-month OS rates, and safety. Results: At the data cutoff (Sep 21, 2022), 33 of the planned 40 patients with an average of 68 years old had been enrolled, including 24 (73%) males and 24 (73%) patients with an ECOG PS score of 1. Twenty-one patients (64%) were previously treated with camrelizumab combined chemotherapy and 12 with other immunochemotherapy. Among the 17 evaluable patients, seven had the best overall response of partial response and nine with stable disease; the ORR was 41%. A total of 22 patients (67%) had treatment-related adverse events (TRAEs), with 12 patients (36%) with grade≥3. The most common TRAEs included white blood cell count decreased (11 patients, 33%), hypokalaemia (9, 27%), and alanine aminotransferase increased (8, 24%). Conclusions: Current results suggested the preliminary efficacy of second-line camrelizumab plus apatinib in patients with immunochemotherapy-treated advanced ESCC, with an acceptable safety profile. The study enrollment is ongoing, and further survival and safety data will be reported in the future. Clinical trial information: NCT03736863.