Dr. Atkins on TFS Outcomes from the HCRN GU16-260 Trial in RCC

Michael B. Atkins, MD, deputy director of the Georgetown Lombardi Comprehensive Cancer Center, Scholl Professor, vice chair, the Department of Medical Oncology, Georgetown University Medical Center, discusses the treatment-free survival (TFS) outcomes from cohort A of the phase 2 HCRN GU16-260 trial (NCT03117309) in patients with advanced renal cell carcinoma (RCC).

Patients enrolled on the study received single-agent nivolumab (Opdivo), and those who achieved a complete or partial response continued on nivolumab monotherapy for up to 96 weeks. Those who had progressive disease or a best response of stable disease received salvage nivolumab plus ipilimumab (Yervoy) for 4 cycles, followed by nivolumab maintenance for up to 48 weeks.

Investigators defined TFS as the time from when treatment stopped due to adverse effects, progressive disease, or protocol completion, to the start of subsequent therapy, Atkins begins. A tumor response to nivolumab alone or nivolumab/ipilimumab was considered a regimen response, and those patients were grouped together for this analysis, Atkins continues.

The overall response rate (ORR) was 35.9%, and the ORRs for patients with favorable-risk, intermediate-risk, and poor-risk disease were 57.9%, 25.6%, and 33.3%, respectively. In all patients, the 3-year progression-free survival (PFS) and overall survival (OS) rates were 14.6% and 68.3%, respectively. Among patients with favorable-risk disease, the 3-year PFS rate was 31.2% and the 3-year OS rate was 96.8%. In those with intermediate- or poor-risk disease, those rates were 7.2% and 56.6%, respectively.

The median TFS was 9.4 months (95% CI, 7.6-11.3) for all patients. In those with favorable-risk disease or intermediate/poor-risk disease, the median TFS was 12.9 months (95% CI, 9.7-16.1) and 8.0 months (95% CI, 5.8-10.2), respectively. Investigators concluded that these findings help support the use of an immunotherapy-only regimen for patients with favorable-risk RCC.