On 22 April the US Food and Drug Administration (FDA) approved Merck & Co’s programmed cell death protein 1 (PD-1) checkpoint inhibitor (CPI) Keytruda (pembrolizumab) in combination with Pfizer’s tyrosine kinase inhibitor Inlyta (axitinib) for the front line treatment of patients with advanced renal cell carcinoma (RCC).

Renal cell carcinoma treatment

This approval marks the second CPI combination regimen that is indicated in this setting, following the first-to-market Opdivo (nivolumab) + Yervoy (ipilimumab) combination marketed by Bristol-Myers Squibb (BMS).

Although BMS’ combination has been available on the market since April 2018, the approval of Merck’s combination two months ahead of the FDA decision date of 20 June 2019 signals that the latter will pose a significant threat to Opdivo + Yervoy in RCC.

Both regimens have significantly improved survival outcomes in the frontline treatment of advanced RCC. Therefore, one of the distinguishing factors for the choice of treatment is expected to be physician familiarity and perspective. Merck has an edge over BMS, as Inlyta has long been indicated for the treatment of advanced RCC and has a convenient administration as oral therapy. In addition, physicians are familiar with the side effects of Inlyta and how to manage them effectively.

On the other hand, Opdivo + Yervoy is not considered to be a tolerable regimen, particularly due to Yervoy’s side effect profile. Therefore, in the face of two equally effective combination regimens, physicians will likely prefer the one that is easier to administer and manage in terms of side effect profile.

A second important distinguishing factor is in the nuances of the labels of the two regimens. Opdivo + Yervoy was not superior to Pfizer’s Sutent (sunitinib malate) in patients with the favourable-risk disease and was therefore approved in patients with intermediate- or poor-risk disease. On the other hand, Keytruda + Inlyta’s clinical benefit was consistently superior to Sutent across all risk groups. Moreover, the clinical data also indicated a correlation between clinical benefit from Opdivo + Yervoy and programmed death-ligand 1 (PD-L1) expression, while Keytruda + Inlyta was effective regardless of PD-L1 status.

GlobalData believes that Keytruda + Inlyta will be a formidable contender to Opdivo + Yervoy in RCC despite being second-to-market and that the combination is well equipped to become the new “standard-of-care” across subpopulations in frontline RCC.