The US Food and Drug Administration (FDA) approved of Sutent (sunitinib), a new targeted anti-cancer treatment for patients with gastrointestinal stromal tumours (GIST), a rare stomach cancer, and advanced kidney cancer.

According to the FDA release, this is the first time that the agency has approved a new oncology product for two indications simultaneously.

Sutent, which received a priority review and was approved in less than six months, is a tyrosine kinase inhibitor working through multiple targets to deprive the tumour cells of the blood and nutrients needed to grow.

"This approval is a major step forward in making breakthrough treatments available for patients with rare and difficult to treat forms of cancer. New targeted therapies such as Sutent are helping FDA expand options for patients for whom there are limited alternatives," said Steven Galson, director of FDA's Centre for Drug Evaluation and Research.

According to the American Cancer Society, about 32,000 new cases of advanced kidney cancer and 5,000 cases of GIST are diagnosed each year.

Sutent was approved for the treatment of patients with gastrointestinal stromal tumours (GIST) whose disease has progressed or who are unable to tolerate treatment with Gleevec, the current treatment for GIST patients. While studying the treatment in patients, researchers conducted an early (interim) analysis of data that showed Sutent delayed the time it takes for tumours or new lesions to grow in patients with this rare type of stomach cancer. Specifically, the median time-to-tumour progression (TTP) for patients treated with Sutent was 27 weeks compared to 6 weeks for patients who were not treated.

FDA also granted accelerated approval for Sutent in the treatment of patients with advanced renal cell carcinoma (RCC). In contrast to the approval for GIST, which was based on the drug's ability to delay the growth of the tumours, this approval was based on Sutent's ability to reduce the size of the tumours in patients. An overall response rate ranging from 26-37 percent was found in patients with metastatic kidney cancer whose tumours had progressed following cytokine-based therapy.

"The approval of this drug for these indications provides compelling evidence that the use of alternative data endpoints allows us to see the benefits of novel therapies earlier in patients," said Richard Pazdur, director of FDA's Office of Oncology Drug Products.

The FDA has a long-standing commitment of providing patients suffering from serious and life-threatening diseases access to safe and effective treatments, in some cases prior to FDA approval. In the GIST clinical trial, significant clinical benefit was determined through an early interim analysis of data, thereby allowing researchers to convert all patients in the trial to treatment. For the RCC indication, the FDA used its accelerated approval process, a regulatory mechanism that expedites drug approvals for serious and life-threatening diseases, added the release.

FDA worked with the product sponsor to offer an expanded access program prior to approval, making the product available to patients not enrolled in a clinical trial. Currently, more than 1700 patients are being treated with Sutent through the expanded access programme

"Expanded access programmes have proven to be an effective way to get treatment to patients, who need it most, especially in cancer. There needs to be a greater awareness among patients and doctors about both the option to participate in clinical research as well as in these expanded access programs in order to make promising new therapies available to as many patients as possible," said Ellen Stovall, president of the National Coalition of Cancer Survivorship.

The most commonly reported Sutent-related side effects included diarrhoea, skin discoloration, mouth irritation, weakness, and altered taste. Patients treated with Sutent also experienced, fatigue, high blood pressure, bleeding, swelling, and taste disturbance. Hypothyroidism was also observed.

Sutent will be distributed by Pfizer Labs, division of Pfizer Inc. in New York.