Clinical characteristics, outcomes and survival of patients with metastatic colorectal cancer on phase I trials: A single center experience from 1999 to 2022.

Abstract

e15593 Background: Metastatic colorectal cancer (mCRC) is a leading cause of cancer mortality. Few treatment options exist for patients who fail to respond to standard therapeutic agents. For patients with good performance status, phase I studies offer a valuable treatment option with a chance of clinical benefit. In this study, we report clinical characteristics, outcomes and survival of patients enrolled in phase I clinical trials at our institution. Methods: Medical records of patients with mCRC enrolled in phase I clinical trials between January 1999 to January 2022 at our institution were reviewed. Patient demographics, clinical characteristics, laboratory values, toxicities and survival time were analyzed. Overall survival (OS) was calculated as date of diagnosis of metastatic disease to death or last follow up. Phase 1 specific OS was analyzed from date of entry to first phase I trial to death. Results: 212 enrollments corresponding to 174 unique patients enrolled in 50 phase 1 clinical trials were reviewed. 53% (n = 112) were females with a median age of 60 years old [range 29-83]. 95% (n = 201) had an ECOG score of 0-1. The clinical benefit rate (stable disease plus partial response) was 35% and ORR was 4.3%. The median OS was 149 weeks, and the phase I OS was 23 weeks. Majority of the patients (53%, n = 110) received 3 or more lines of chemotherapy prior to phase I trial. In a univariable (UVA) model, the factors associated with better clinical outcome were WBC < 10.8 (P < 0.001), Hb > 12 (p = 0.011), ECOG score 0 or 1 (p = 0.005), baseline AST < 50 (p = 0.006), baseline albumin > 3.5 (p < 0.001), baseline LDH < 305 (p < 0.001). Conclusions: Phase I trials offer a reasonable option for patients with metastatic CRC. Our experience sheds light on the potential for improved outcomes in terms of survival. The survival of patients is at par with those used in late-stage disease including regorafenib and trifluridine/tipiracil. As expected, normal baseline lab parameters and better PS affect survival. Further modeling will be continued.