The FOXFIRE Combined Analysis assessed the Overall Survival (OS) data from three randomised, controlled clinical studies FOXFIRE, FOXFIRE Global and SIRFLOX. These studies compared SIR-Spheres® Y-90 resin microspheres in combination with standard-of-care chemotherapy to chemotherapy alone in first-line treatment of metastatic colorectal cancer (mCRC).
The combined OS analysis was based on pooled data of 1,103 patients and examined a potential survival benefit from the addition of SIR-Spheres Y-90 resin microspheres to current chemotherapy. All three studies recruited chemotherapy-naïve patients with unresectable liver metastases from primary colorectal cancer, with or without limited extra-hepatic disease.
The data from the FOXFIRE Combined Analysis were presented in June 2017at American Society of Clinical Oncology (ASCO) and published in the Lancet Oncology in August 2017.1
SIRFLOX study design
The SIRFLOX study was the first large-scale, randomised controlled trial (RCT) of 530 chemotherapy-naïve patients with liver-only or liver-dominant mCRC which examined whether the combination of SIR-Spheres Y-90 resin microspheres with first-line chemotherapy was more effective than chemotherapy alone. The SIRFLOX study results were published in Journal Clinical of Oncology in early 2016.2 There was no statistically significant improvement in PFS at any site with the addition of SIR-Spheres Y-90 resin microspheres, a finding that was not unexpected with a liver-directed treatment. However, the risk of first progression in the liver as per competing risk analysis remained significantly lower for patients receiving SIR-Spheres Y-90 resin microspheres. The improvement was 7.9 month with an HR of 0.69 corresponding to a 31% reduction in risk of progression in the liver at any point in time.2
FOXFIRE study design
The FOXFIRE study randomised 364 patients, with unresectable, liver-only or liver-predominant mCRC, in 32 UK cancer centres. The study was initiated in 2010 by the Oxford Oncology Clinical Trials Office (OCTO) in collaboration with the UK National Cancer Research Institute and completed patient enrolment in 2014.3 In FOXFIRE, the use of the biologic agents bevacizumab or cetuximab were allowed at the investigator’s discretion and were stratified accordingly.
FOXFIRE Global study design
The FOXFIRE Global study enrolled 209 patients. The study began in 2013 in a network of more than 80 centres in Australia, New Zealand, Asia Pacific, Israel, Western Europe and the United States. The study completed patient enrolment in 2014.
1. Wasan HS et al. Lancet Oncol 2017; 18: 1159-71.
2. van Hazel GA et al. J Clin Oncol 2016; 34:1723–31.
3. Dutton SJ et al. BMC Cancer 2014; 14: 497.