- Merck & Co.'s Keytruda, when used as a first-line treatment with Pfizer's Inlyta, significantly improved overall survival (OS) for the most common form of kidney cancer, according to pivotal Phase 3 data issued Thursday.
- Dubbed KEYNOTE-426, the study assessed whether Keytruda plus Inlyta would beat out Sutent in treating advanced or metastatic renal cell carcinoma. While the study is ongoing, the combo significantly outperformed the monotherapy on OS, considered the gold standard of effectiveness in cancer studies, as well as progression free survival and objective response rate.
- Notably, the responses were consistent across all risk groups and at all levels of PD-L1 expression. Merck intends to present more complete KEYNOTE-426 results at an upcoming medical and also submit them to regulatory authorities worldwide.
Pfizer's already found success in the kidney cancer market with Sutent (sunitinib malate), an oral multi-kinase inhibitor which holds indications for advanced RCC and certain pancreatic tumors that can't be removed through surgery. The drug first gained approval in 2006, and quickly became the most prescribed oral therapy for metastatic RCC in the U.S.
More recently, eye-catching data presented at the 2018 American Society of Clinical Oncology conference showed advanced kidney cancer patients taking Sutent could skip having a kidney removal without that negatively affecting their overall survival chances.
Still, Sutent has drawbacks. It carries a black box waring for liver toxicity. It also will lose patent protection in the U.S. in 2021.
As Sutent inches toward its patent cliff, Pfizer has been working to bring newer kidney cancer therapies to market. Inlyta (axitinib), a tyrosine kinase inhibitor (TKI), is one such therapy, gaining approval in 2012 for advanced RCC who failed one prior systemic treatment.
And on the first-line front, Pfizer is looking to drug pairings. The big pharma is supplying Inlyta for the KEYNOTE-426 study, and is running a Phase 3 trial testing it as a combo regimen with the immuno-oncology drug Bavencio (avelumab). Last month, Pfizer and partner Merck KGaA announced positive interim data from that trial, showing the combo significantly beat out Sutent on improving PFS for patients with PD-L1 expression greater than 1%.
The early success in KEYNOTE-426 further underscores that Pfizer has a few promising options for its next play in kidney cancer. Yet Brad Loncar, head of Loncar Investments and biopharma investor, noted one route may be the better business decision.
PD-1s work with Pfizer’s Inlyta in RCC. We learned that w/ Pfizer’s Bavencio (PFS) and today w/ Merck’s Keytruda (PFS & OS).— Brad Loncar (@bradloncar) October 18, 2018
In the future Pfizer should offer a discount for the entire combo using their two drugs and cut Merck out. That’s where this should be headed one day IMO.
In an email to BioPharma Dive, Pfizer said results from KEYNOTE-426 and the Bavencio-Inlyta studies "highlight the benefits of a combination of an immunotherapy with a tyrosine kinase inhibitor in the first-line treatment of advanced renal cell carcinoma. This is good news for patients in need of treatment options and may ultimately represent a new standard of care for the field, pending regulatory approvals."
"We are in discussions with health authorities to bring the Bavencio-Inlyta combination therapy to patients with advanced RCC as quickly as possible," the company added.
Correction: A previous version of this article incorrectly stated Inlyta was co-developed with Merck KGaA.