The US Food and Drug Administration (FDA) announced on Monday that it had approved Afinitor oral tables (everolimus) for the treatment of advanced kidney cancer in patients where the disease continued to progress after treatment with other drugs.

Afinitor is manufactured by Novartis International AG of Basel, Switzerland.

Dr Robert Justice, director of the Division of Drug Oncology Products in the FDA’s Center for Drug Evaluation and Research (CDER) said:

“Afinitor provides an option for patients with advanced renal cell cancer after failure of treatment with the cancer therapies sunitinib [Sutent, from Pfizer] or sorafenib [Nexavar, from Bayer].”

“Targeted cancer therapies like Afinitor have increased the number of months patients can live without the tumor progressing,” he added.

The most common form of kidney cancer is renal cell carcinoma, which starts in the lining of the tiny tubules inside the kidney that clean the blood by filtering out the waste products of metabolism and other body processes. It accounts for about 2 per cent of all new cancers and rates of new cases are going up worldwide, partly because of smoking and obesity, according to sources cited in a Novartis press statement.

Renal cell carcinoma resists standards treatments like radiotherapy and chemo, and treatment usually starts with surgical removal of the affected kidney. If the cancer hasn’t spread outside of the affected kidney, five year survival can be as much as 60 to 70 per cent, but it is much lower if the cancer has spread.

Afinitor is a kinase inhibitor: it stops tumors growing by blocking a specific protein called mTOR, the mammalian target of rapamycin. This action stops the cell to cell communications that help cancer cells to grow, divide and metabolize. In contrast, Sutent and Nexavar are multiple kinase inhibitors and work on several targets at the same time.

The FDA approval relied on the results of the RECORD-1 clinical trial that tested the safety and effectiveness of Afinitor given as a daily oral dose against placebo. The trial was stopped early because interim results showed that patients taking the drug experienced delayed tumor growth and spread compared to those who did not. Also, disease progression was delayed for about five months in 50 per cent of the patients who took the drug compared to only 2 months for those who did not.

According to the FDA announcement, the most frequent adverse reactions (1 in 5 patients had them) included: “inflammation in the mouth, loss of strength, diarrhea, poor appetite, fluid buildup in the extremities, shortness of breath, coughing, nausea, vomiting, rash, and fever“.

Lab tests of blood samples also showed that at least half the patients were anemic, had low white blood counts, high cholesterol, high blood sugar and high triglycerides (blood fats), said the agency.

Dr Robert J Motzer, attending physician, Memorial Sloan-Kettering Cancer Center, New York and principal investigator of the trial told the press that:

“This approval provides a new and useful tool for treating advanced renal cell cancer, representing an important step forward in managing this disease.”

“New treatment options are vital to help us continue to offer patients with advanced kidney cancer new ways to battle their difficult-to-treat disease. Based on clinical trial data, this option should be considered when sunitinib or sorafenib fail.”

Novartis said in a press release that it has also filed for approval of Afinitor in the European Union, Switzerland and Japan, as well as with other regulatory agencies globally and that Phase III trials are underway to explore the potential of the drug in treating several other cancers.

David Epstein, President and CEO, Novartis Oncology, Novartis Molecular Diagnostics said:

“We continue to study Afinitor in kidney cancer, and through a broad clinical program to explore its potential in many other tumor types.”

Sources: FDA, Novartis.

Written by: Catharine Paddock, PhD