Dr. Plimack on Updated Findings of the KEYNOTE-426 Study in RCC

Elizabeth R. Plimack, MD, MS, chief of the Division of Genitourinary Medical Oncology, director of Genitourinary Clinical Research, and professor in the Department of Hematology/Oncology, at Fox Chase Cancer Center, discusses the updated findings from the phase 3 KEYNOTE-426 study in patients with previously untreated, advanced renal cell carcinoma (RCC).

Patients enrolled in the study had advanced RCC and were treated with either the combination of pembrolizumab (Keytruda) and axitinib (Inlyta) or sunitinib (Sutent). Some of interesting findings from the updated analysis presented at the 2020 ASCO Virtual Scientific Program are that in the favorable-risk group, investigators have yet to see the overall survival (OS) curves split, says Plimack. Investigators hope to see those results with time, but this may not happen because this is a group of patients who tend to do very well overall, says Plimack. Specifically, the hazard ratio for OS in the favorable-risk group was 1.06 (95% CI, 0.60-1.86). Whether the combination treatment makes a difference in the favorable-risk group remains to be seen.

For the intermediate- and poor-risk groups, the difference in OS, progression-free survival (PFS), and response rate is clear, says Plimack. The hazard ratio for OS was 0.63 (95% CI, 0.50-0.81) and for PFS, it was 0.69 (95% CI, 0.56-0.84). The overall response rate was 55.8% with the combination versus 35% with sunitinib.

Additionally, an exploratory analysis was also conducted in which depth of response (DOR) was assessed, as well as its relationship to OS in the subgroup of patients who made it to the 6-month mark. Results showed that with pembrolizumab/axitinib, there was a relationship between DOR and survival; the deeper the response, the longer patients lived, explains Plimack. That relationship was not clear in the sunitinib arm. From a clinical perspective, that means that a patient with a near complete response or a deep response is likely to do very well on the doublet regimen and that is important to know as that information can be used when counseling patients, concludes Plimack.

<<< 2020 ASCO Virtual Scientific Program