Abstract 422P
Background
Colorectal cancer (CRC) is the third most common cancer. There are limited therapeutic options for the treatment of advanced CRC which fail first-line chemotherapy. Pre-clinical and phase I/II studies have shown that the combined application of the irinotecan and raltitrexed has significant synergistic effect and acceptable toxicity. The aim of this multicenter study was to assess the efficacy and toxicity of second-line raltitrexed plus irinotecan in Chinese patients with advanced colorectal cancer.
Methods
This is an open-label, single-arm, multicenter, phase II trial (Registered in clinicaltrials.gov with NCT03053167). Brief inclusion criteria: patients aged 18 to 75 years with locally advanced or metastatic CRC after failure of oxaliplatin and fluorouracil therapy. Enrolled patients received irinotecan (180 mg/m2, d1) and raltitrexed (3 mg/m2, d1) each 21-day cycle until disease progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were disease control rate (DCR), objective response rate (ORR), overall survival (OS), quality of life (QOL) and safety. In all, 100 patients were required for primary point testing.
Results
Between October 2016 and May 2020, a total of 108 patients were screened for enrollment, The median age was 61 years (range: 38-75 years), ECOG 1 scored 67.6%. A total of 502 cycles were completed, with an average of 4.6 cycles and a median of 4 cycles. 97 patients reached the PFS, and 83 patients reached the OS. 108 patients were evaluable and ORR was 17.6%, DCR was 76.9%. The median follow-up time was 15.2 months at data cut-off on Oct 9, 2020. Median PFS was 4.5 months and median OS was 12.7 months. The most common adverse events were elevated alanine aminotransferase increased (47.1%), aspartate aminotransferase increased (44.3%), fatigue (23.9%), diarrhea (31.3%), thrombocytopenia (30.6%), and hypohemoglobin (30.6%). Most of the adverse events were grade I/II, and there were no treatment-related death.
Conclusions
We have demonstrated that irinotecan plus raltitrexed is active and feasible in patients with second-line treatment in advanced colorectal cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.