2198 - SOLSTICE, a phase 3, randomized, open label study of trifluridine/tipiracil+bevacizumab (bev) versus capecitabine+bev for the 1L treatment of patients with unresectable metastatic colorectal cancer (mCRC) who are not candidates for intensive therapy

Background

A phase 2 study in first-line mCRC patients non-eligible for intensive therapy (TASCO1, NCT02743221) treated with trifluridine/tipiracil-bev (TT-B, n = 77) or capecitabine-bev (C-B, n = 76), reported a longer median PFS with TT-B (9.2 months) than with C-B (7.8 months). The hazard ratio (HR) for progression between TT-B and C-B was 0.71 (95% CI, 0.48 to 1.06). Preliminary median OS was 18 months with TT-B and 16.2 months with C-B (HR, 0.56; 95% CI 0.32 to 0.98). The safety of TT-B was found to be acceptable with, for all-grade toxicities, more gastrointestinal and hematologic toxicities but a much lower rate of hand-foot syndrome than C-B (serious febrile neutropenia 3.9% with TT-B or C-B and diarrhoea grade 3-4: 1.3% with TT-B vs. 7.9% with C-B). Following this phase 2 trial, a global confirmatory phase 3 trial (SOLSTICE) has been initiated.

Trial design

This phase 3, international, open-label, randomized study will include 854 first-line mCRC-patients, not candidate for intensive oxaliplatin- or irinotecan-based chemotherapy and non-eligible for curative resection, according to investigator’s judgment and in relation with age, performance status (PS), low tumour burden, comorbidities or non-clinical reasons. The stratification factors are ECOG PS (0 vs 1 vs 2), tumour localization (right vs left) and reason for non-eligibility to intensive therapy. Patients will be randomly allocated to trifluridine/tipiracil (35 mg/m² given orally bid on days 1–5 and 8–12 in a 28-day cycle) plus bev (5 mg/kg on days 1 and 15 of a 28-day treatment cycle) or capecitabine (1250 or 1000 mg/m²/dose bid on days 1-14 in a 21-day) plus bev (7.5 mg/kg on day 1 in a 21-day treatment cycle). The primary endpoint is PFS and the key secondary endpoint is OS. Other secondary endpoints include safety and quality of life assessed by EORTC QLQ-C30 and EQ-5D questionnaires. Patients will also undergo comprehensive geriatric assessment using G8 questionnaire and Charlson Comorbidity Index at baseline. Inclusion of the first patient was done in March 2019. It is planned to open approximately 200 centers in 25 countries.

Clinical trial identification

NCT03869892; March 11, 2019.

Editorial acknowledgement

Legal entity responsible for the study

Institut de Recherches Internationales Servier.

Funding

Institut de Recherches Internationales Servier.

Disclosure

T. Andre: Advisory / Consultancy, Travel / Accommodation / Expenses: Roche/Genentech, Amgen, Bristol-Myers Squibb, MSD Oncology and Servier, and honoraria from Roche/Genentech, Sanofi, Baxter, Bayer, Bristol-Myers Squibb, Amgen, MSD Oncology, Servier, XBiotech, and Novartis. M.P. Saunders: Advisory / Consultancy: Roche, Merck, Servier, Amgen, Sanofi, and Eisai. A. Kanehisa: Full / Part-time employment: IRIS. E. Gandossi: Full / Part-time employment: IRIS. R. Fougeray: Full / Part-time employment: IRIS. N. Causse-Amellal: Full / Part-time employment: IRIS. A. Falcone: Advisory / Consultancy, Research grant / Funding (institution): Amgen, Bayer, Merck, MSD, Roche, Lilly, Servier, Bristol.