The vascular endothelial growth factor receptor-2 (VEGFR-2) tyrosine kinase inhibitor apatinib significantly prolonged overall survival in patients with advanced gastric cancer compared with placebo, according to the results (abstract 4003) of a phase III study presented at the 2014 American Society of Clinical Oncology (ASCO) Annual Meeting, held May 30–June 3 in Chicago.
“Apatinib is the first small molecule–targeting VEGFR to show a survival benefit in advanced gastric cancer,” said Shukui Qin, MD, of PLA Cancer Center of Nanjing Bayi Hospital in Nanjing, China. “Apatinib monotherapy is a new treatment option for advanced gastric cancer patients who failed to second line of chemotherapy.”
According to Qin, more than 80% of patients who are diagnosed with advanced gastric cancer in China require chemotherapeutic treatment. Additionally, there is a strong unmet need for patients with advanced gastric cancer who fail second-line chemotherapy.
This phase III trial included patients with advanced gastric cancer who had failed prior second-line chemotherapy. The patients were randomly assigned 2:1 to 850-mg apatinib or placebo. The primary endpoint of the study was overall survival.
Results of the study revealed an almost 2-month overall survival advantage for patients assigned apatinib. The median overall survival was 6.5 months for apatinib compared with 4.7 months for placebo (P = .0027).
Progression-free survival endpoints also showed significant differences in favor of apatinib in both the full analysis set (3.6 vs 1.8 months; P < .001) and the per-protocol set (2.8 vs 1.9 months; P < .001) of patients.
The researchers also found that apatinib increased the overall response rate (2.84% vs 0%) and the disease control rate (42.05% vs 8.79%; P < .001) compared with placebo.
Patients assigned apatinib experienced significantly more adverse events compared to patients on placebo (P = .0038). However, apatinib was not found to increase severe adverse events.
Patients assigned apatinib had significantly more leukocytopenia (40.34% vs 8.79%; P < .0001), neutropenia (37.5% vs 9.89%; P < .001), and thrombocytopenia (25% vs 6.59%; P = .0002). Apatinib was also associated with significant increases in proteinuria, hypertension, and hand-foot syndrome.