Results from a phase I clinical trial with a combination of X4P-001-IO plus axitinib in patients with clear cell renal cell carcinoma (ccRCC) were presented at the European Society of Medical Oncology (ESMO) 2017 Congress in Madrid, Spain this week. The early phase results demonstrated encouraging disease control rates and durable responses with the new combination treatment, and recruitment in the phase II expansion study is currently underway.
X4P-001-IO blocks the C-X-X receptor 4 (CXCR4), which modulates the immune system and development of new blood vessels (angiogenesis) by activating various immune cells, including T-cells, dendritic cells, and myeloid-derived suppressor cells. Through its action on the CXCR4 receptor, it is thought that X4P-001-IO can improve the anti-tumour responses of the immune system. Axitinib (Inlyta) is a tyrosine kinase inhibitor (TKI) for second-line treatment of advanced renal cell carcinoma.
All 16 patients with advanced ccRCC in the phase I study received at least one prior treatment, and 69% of patients received at least two. The combination of X4P-001-IO plus axitinib was proven to improve disease control rate in 92% and objective response rate in 25% of patients who completed the study (n=12). The most frequent treatment-related adverse events (AEs) in patients included diarrhoea, hypertension, fatigue, nausea, headache, decreased appetite, and vomiting.
“The high disease control rate and clinical responses in previously treated patients with late-stage clear cell renal cell carcinoma underscore the rationale for investigating the therapeutic potential of CXCR4 inhibition plus VEGFR inhibition,” said Michael Atkins, MD, Deputy Director, Georgetown-Lombardi Comprehensive Cancer Center in Washington, DC and William M. Scholl, Professor of Oncology at Georgetown University School of Medicine in a press release. “The preliminary results shown in this clinical study are very encouraging and support continued investigation of this approach.”