Experimental Third-Line Treatment Slows Cancer Progression in Patients with Advanced Colorectal Cancer

Treatment with famitinib, a multi-targeted tyrosine kinase inhibitor, led to a small but statistically significant improvement in progression-free survival (PFS) in patients with advanced, previously treated metastatic colorectal cancer, Chinese investigators reported at the 2015 Gastrointestinal (GI) Cancers Symposium.

In a phase 2 study, famitinib monotherapy was associated with a median PFS of 2.8 months compared with 1.5 months in patients treated with placebo. Subgroup analysis showed a similar PFS advantage in favor of famitinib irrespective of gender, patient age or extent of metastatic involvement. An improvement in overall survival was not observed, but a trend toward prolonged median overall survival was noticed in the subgroup of patients who had completed more cycles of therapy.

“Famitinib, as a single-agent treatment, improved the PFS by 1.3 months in patients with advanced, metastatic colorectal cancer,” said Xu, a medical oncologist at Sun Yat-Sen University Cancer Center in Guangzhou, China. “Famitinib demonstrated a similar safety profile with other molecular anti-VEGFR agents."

The most common adverse events were neutropenia, thrombocytopenia, proteinuria, hypertension and hand-foot syndrome, which were tolerable and manageable.

Patients with advanced/metastatic colorectal cancer have few effective treatment options. In China, standard first- and second-line chemotherapeutic regimens are FOLFOX and FOLFIRI. Erbitux (cetuximab) and Avastin (bevacizumab) are the only targeted agents approved for treatment of advanced/metastatic colorectal cancer.

Targeting tumor angiogenesis, famitinib is a small-molecule inhibitor of VEGFR2, c-Kit and PDGFR. Xu and colleagues sought to determine in a multicenter trial whether famitinib could improve PFS in patients with advanced colorectal cancer that had progressed through at least two prior lines of chemotherapy.

Investigators randomized 154 patients in 2-to-1 ratio to faminitib or placebo, and treatment continued until disease progression or development of unacceptable toxicity. The patients had a median age of about 55 years, and 60 percent had received more than three prior lines of therapy.

Two patients in the famitinib group achieved partial responses and 53 had stable disease, resulting in a disease control rate of nearly 60 percent. No objective responses were observed in the placebo group, and 16 patients had stable disease, leading to a disease control rate of 31.4 percent.