19 October 2018 - - A pivotal Phase 3 KEYNOTE-426 trial investigating US-based biopharmaceutical company Merck's (NYSE: MRK) Keytruda (pembrolizumab), Merck's anti-PD-1 therapy, in combination with Inlyta (axitinib), Pfizer's (NYSE: PFE) tyrosine kinase inhibitor, met both primary endpoints of overall survival and progression-free survival in the first-line treatment of advanced or metastatic renal cell carcinoma, the most common type of kidney cancer, the company said.

Based on the first interim analysis by the independent Data Monitoring Committee, the Keytruda plus Inlyta combination resulted in statistically significant and clinically meaningful improvements in OS and PFS, compared to sunitinib monotherapy.

The study also met the key secondary endpoint of objective response rate, with significant improvements for the Keytruda and Inlyta combination compared with sunitinib monotherapy.

Results for OS, PFS and ORR were consistent regardless of PD-L1 expression and across all risk groups.

The safety profile of Keytruda and Inlyta in this trial was generally consistent with that observed in previously reported studies for each therapy.

These results will be presented at an upcoming medical meeting and submitted to regulatory authorities worldwide.

KEYNOTE-426 is a randomised, double-arm, Phase 3 trial (ClinicalTrials.gov, NCT02853331) evaluating the safety and efficacy of Keytruda in combination with Inlyta as first-line treatment for advanced or metastatic RCC compared to sunitinib.

The dual primary endpoints of the study were OS and PFS, and the key secondary endpoint was ORR.

Additional secondary endpoints were disease control rate, number of participants who experienced or discontinued the study due to an adverse event, duration of response, PFS at 12, 18 and 24 months and OS at 12, 18 and 24 months.

In the trial, 861 patients were randomly assigned to receive Keytruda 200 mg intravenously every three weeks plus Inlyta 5 mg orally twice daily for up to 24 months, or sunitinib 50 mg orally once daily for four weeks followed by no treatment for two weeks, continuously.

Renal cell carcinoma is by far the most common type of kidney cancer; about 9 out of 10 kidney cancers are renal cell carcinomas.

RCC is about twice as common in men as in women.

Modifiable risk factors include smoking, obesity, workplace exposure to certain substances and high blood pressure.

There are expected to be approximately 403,262 cases of kidney cancer diagnosed worldwide in 2018 and about 175,098 people will die from the disease. In the US alone, there will be an estimated 63,340 new cases of kidney cancer diagnosed in 2018 and about 14,970 people will die from the disease

Keytruda is an anti-PD-1 therapy that works by increasing the ability of the body's immune system to help detect and fight tumor cells. Keytruda is a humanised monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, thereby activating T lymphocytes which may affect both tumor cells and healthy cells.