Abstract 442P
Background
Camrelizumab is a selective, humanized, high-affinity immunoglobulin G4/κ monoclonal antibody against PD-1. Apatinib is a novel small-molecule TKI that exerts its antitumour effect by targeting VEGFR-2. Anti-angiogenic agents can modulate the immunosuppressive tumour microenvironment, which contributes to resistance to anti-PD-1/PD-L1 treatment. This study assessed the safety and efficacy of camrelizumab and apatinib as combination therapy in patients with relapsed / metastatic gastric cancer (GC) and colorectal cancer (CRC).
Methods
We enrolled patients with previously treated (at least 2 lines of systemic therapy) advanced GC or CRC. ECOG PS 0-1, and no prior immuno-oncology (IO) therapy. Eligible patients were planned to receive camrelizumab 200 mg day1 and 15, apatinib 250 mg day1-28, every 4 weeks until disease progression or intolerable toxicity. The primary endpoint was investigator-assessed objective response rate (ORR). Secondary endpoint was progression free survival (PFS), overall survival (OS), safety, tolerability and disease control rate (DCR).
Results
Until April 2020, 20 CRC patients and 15 GC patients were enrolled in the study. The median number of prior treatment lines was 3 (range 3-5). Liver metastases were observed in 27 (77.1%) patients, 7 (20.0%) had lung metastases, 8 (22.9%) had abdominal lymph node metastases, and 10 (28.6%) had metastases at other sites. 16 (80.0%) CRC patients had received prior treatment with anti-angiogenic agents. In the GC cohort ,3 patients had a partial response (PR), 8 had stable disease (SD) and 4 had progressive disease (PD). ORR in this cohort was 20.0% and DCR was 80.0%. In the CRC cohort, 6 patients had PR, 10 had SD and 4 had PD. ORR was 30.0 % and DCR was 80.0%. Median estimates for PFS and OS for both cohorts were not reached. In all patients, grade ≥3 treatment-related adverse events (TRAEs) included neutrophil decrease (2.3%, increased ALT (13.3%), increased AST (13.3%), fatigue (5.7%), increased blood bilirubin (6.7%), hypertension (11.4%,), and proteinuria (6.7%). None of the TRAEs were fatal.
Conclusions
Camrelizumab and low-dose apatinib combination therapy demonstrated manageable toxicity and might offer a new promising choice for those patients with GC and CRC who have failed standard therapy.
Clinical trial identification
NCT04067986.
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Jiangsu Hengrui Medicine Co. (Shanghai) Ltd.
Disclosure
All authors have declared no conflicts of interest.