TAS-102, Irinotecan, and bevacizumab in pre-treated metastatic colorectal cancer (TABAsCO), a phase II clinical trial.

BACKGROUND

The efficacy of FOLFIRI plus an antiangiogenesis biologic agent as 2nd line therapy for metastatic colorectal adenocarcinoma is limited. TAS-102 is a novel oral antimetabolite with a distinct mechanism of action from fluoropyrimidines. We evaluated the antitumour efficacy of TAS-102, irinotecan and bevacizumab in patients with pre-treated, advanced colorectal adenocarcinoma in a multicenter, phase II, single-arm study.

METHODS

Patients with advanced colorectal adenocarcinoma who had progressed after oxaliplatin and fluoropyrimidine and were eligible for treatment with bevacizumab were treated with irinotecan, bevacizumab, and TAS-102 in 28-day cycles. The primary endpoint was progression-free survival (PFS).

RESULTS

We enrolled 35 evaluable patients. The study was positive. The median PFS was 7.9 (90% CI 6.2-11.8) months (vs. 6 months in historical control, p = 0.018). The median overall survival was 16.5 (90% CI 9.8-17.5) months. Sixty-seven per cent of patients experienced grade 3 or higher treatment-related adverse events. The most common toxicities were hematological (neutropenia) and gastrointestinal (diarrhoea, nausea, and vomiting).

CONCLUSIONS

Irinotecan, TAS-102 and bevacizumab is an active 2nd line therapy for patients with metastatic colorectal adenocarcinoma. Neutropenia is common and can affect dose density/intensity mandating use of G-CSF. A randomized study versus standard-of-care therapy is warranted.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT04109924.