Hans Hammers, MD, PhD

THE COMBINATION of checkpoint inhibitors and vascular endothelial growth factor (VEGF) inhibitors is attractive in renal cell carcinoma, said formal discussant of this trial, Hans Hammers, MD, PhD, of the University of Texas Southwestern Medical Center in Dallas. 

“Twenty-one percent of patients win the lottery and get a durable response to nivolumab [Opdivo], while the vast majority get no benefit. The hope is that combination with VEGF inhibitors will amplify and unmask the effectiveness of programmed cell death protein 1 (PD-1) or programmed cell death ligand 1 (PD-L1) inhibition,” he said. 

“High response rates with such combinations are encouraging. The combinations of pembrolizumab (Keytruda)/pazopanib (Votrient) and nivolumab/pazopanib both had dose-limiting toxicity early on. We have to be cautious with PD-1/PD-L1 inhibitors plus a VEGF tyrosine kinase inhibitor. The combination studied by Atkins et al is more selective than these other combinations,” Dr. Hammers explained. 

The trend for improved progression-free survival in the PD-L1–positive tumors is promising, and the toxicity with the combination is not much different from that with atezolizumab (Tecentriq) alone. 

“This trial presented interesting data with regard to biomarkers and the signal for T-cell infiltration with the myeloid component. The high response rates seen are quite impressive. We need to see how the data look after longer follow-up. Will we just see a progression-free survival benefit or also move the tail of the curve?” ■

DISCLOSURE: Dr. Hammers has served as an advisor to Bristol-Myers Squibb, Pfizer. Novartis, Exelixis, and Bayer and has received clinical trial support from Bristol-Myers Squibb and Merck.