Among patients with advanced melanoma, presence of higher levels of the protein vascular endothelial growth factor (VEGF) in blood was associated with poor response to treatment with the immunotherapy ipilimumab, according to a study published in Cancer Immunology Research. The study suggests combining immunotherapy with VEGF inhibitors, also known as angiogenesis inhibitors, may be a potential option for these patients.
The immune-checkpoint inhibitor ipilimumab works by boosting the body’s immune system to combat melanoma. VEGF is a protein that promotes new blood vessel formation and growth, a process called angiogenesis, thus providing nutrients to the growing tumor. The study found that among patients who had late-stage melanoma, those who had high levels of VEGF in their blood prior to treatment with ipilimumab had decreased clinical benefit and poor overall survival compared with those who had lower levels of VEGF.
Researchers conducted retrospective analyses of blood samples collected from 176 patients with metastatic melanoma, before and after they were treated with ipilimumab. Patients were 16 to 91 years old, and most had stage 4 disease.
VEGF levels in patients’ blood ranged from 0.1 to 894.4 picograms per milliliter (pg/ml). The investigators determined 43 pg/ml to be the cutoff value, and evaluated patient responses to treatment as those whose pretreatment VEGF levels were greater than (VEGF-high) or less than (VEGF-low) the cutoff value. They found that at 24 weeks after starting ipilimumab treatment, 41% of the VEGF-low patients experienced clinical benefit, compared with 23% of the VEGF-high patients. The median overall survival for VEGF-low patients was 12.9 months, compared with 6.6 months for VEGF-high patients. Read the study abstract.
