FDA Slaps Breakthrough Tag on Eisai, Merck's Combo Renal Cell Carcinoma Drug

Merck and development partner Eisai Co., Ltd. snagged Breakthrough Therapy Designation from the U.S. Food and Drug Administration for the combination treatment the companies are developing for the potential treatment of patients with advanced and/or metastatic renal cell carcinoma (RCC).

The companies have combined Eisai’s Lenvima, a multiple receptor tyrosine kinase inhibitor and Merck’s anti-PD-1 drug Keytruda. The FDA’s Breakthrough Therapy Designation was based on results of a RCC cohort in Study 111, a multicenter, open-label phase 1b/2 clinical study assessing the safety and efficacy of the combination treatment in subjects with selected solid tumors. The primary objective in the study is to determine the maximum tolerated dose of the combined drugs. The Study III Phase Ib/II trial has dosed patients with unresectable solid tumors, including renal cell carcinoma, endometrial cancer, non-small cell lung cancer, urothelial cancer, squamous cell head and neck cancer and melanoma. The patients in the trial had progressed after treatment with approved therapies or for which there are no standard effective therapies available.

The Phase II part of the trial is underway with patients who had select solid tumors with 0-2 prior lines of systemic therapy. The primary endpoint of the Phase II part is objective response rate at 24 weeks after treatment began.

Renal cell carcinoma comprises approximately 90 percent of all malignancies of the kidney. There were an estimated 63,990 new cases of RCC in the United States last year. Of those, it is estimated that 14,440 will die from the disease. Approximately 25 to 30 percent of patients are estimated to present with metastatic disease at time of diagnosis. The advanced form of RCC is difficult to treat with surgery and standard care is molecular targeted drug therapy. Merck and Eisai said there is still unmet need for treatments in this patient population.

Roy Baynes, chief medical officer of Merck Research Laboratories, said the FDA designation will provide the two companies with the opportunity to accelerate efforts in developing the potential treatment. Breakthrough Therapy Designation is intended to expedite development and review of drugs for serious or life-threatening conditions.

"We remain committed to understanding the full potential of Keytruda across cancers and treatment settings, and our collaboration with Eisai is one of the many ways we are executing on this commitment to helping more patients," Baynes said in a statement.

Takashi Owa, chief medicine creation officer for Eisai’s oncology business group, said the Breakthrough Therapy Designation was encouraging for the experimental combination treatment. Like counterpart Baynes, Owa said the potential treatment is important to patients with advanced and/or metastatic renal cell carcinoma.

This is the second Breakthrough Therapy Designation for Lenvima and the 12th such designation for Keytruda.

Earlier this month, Keytruda became the first anti-PD-1 therapy approved in Japan for the treatment of patients with radically unresectable urothelial carcinoma who progressed after cancer chemotherapy.