Abstract 83P
Background
Maintenance therapy can extend patient survival and improve patient quality of life. We aimed to evaluate the efficacy and safety of cetuximab plus raltitrexed (Saiweijian®) as first-line maintenance therapy in Chinese patients with RAS wild-type mCRC.
Methods
This is a prospective, open-label, single-arm, multi-center, phase II trial registered in clinicaltrials.gov with NCT04241731. Fifty patients were required according to statistical sample size. Enrolled patients disease stable or improved while on first-line use of FOLFOX/FOLFIRI with cetuximab for 4-6 months were treated with cetuximab plus raltitrexed (cetuximab 500mg/kg, d1,q2w, raltitrexed 2.5mg/m2,d1,q2w)until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS) of maintenance therapy, the secondary endpoints were PFS of first-line therapy,overall survival (OS),quality of life (QOL) and safety.
Results
Between May 2020 and May 2024, 31 patients were enrolled. The median age was 62 years(range:44-81 years), ECOG PS 0 scored 61.3%. A total of 198 maintenance therapy cycles were completed,24 patients reached the primary endpoint, the median PFS（mPFS）of maintenance therapy was 7.1 months (95% CI: 3.2,12.0), and the mPFS of first-line therapy was 12.7 months (95% CI: 8.6,16.8).The median OS（mOS ) was not observed yet.Currently,the ORR of maintenance therapy was 51.7%, and the DCR was 79.3%. Adverse events (AEs) were mostly grade 1/2, and no SAEs or cardiotoxic events occured. The most common AEs were rash (35.5%), alanine aminotransferase increased (29.0%), glutamyl transferase increased (22.6%), anemia (22.6%), neutropenia (19.4%), hypoalbuminaemia (19.4%), leukopenia (16.1%) and fatigue (12.9%).
Conclusions
Our interim results suggest that cetuximab plus raltitrexed could be an efficient and safe first-line maintenance therapy option for patients with mCRC. This trial will progress as planned.
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.