The Food and Drug Administration (FDA) has recently approved Pfizer’s drug sunitinib (Sutent) for the treatment of the rare and slow growing cancer known as pancreatic neuroendocrine tumor (pNET). The drug is approved for use in patients who cannot be treated with surgery or who have had their tumor spread to distant organs. This cancer is very rare and the FDA reports that it affects only about 1,000 patients in the United States each year. Steve Jobs, CEO of Apple Inc., was diagnosed with the disease in 2004 and has taken several medical leaves of absence for treatment which has given media attention to pNET. Sutent is a tyrosine kinase inhibitor and works by blocking growth factors that bind to vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR). These receptors are expressed by pNET and many other types of tumors and help the cancers grow and spread to other parts of the body. A few weeks ago, the FDA approved Novartis’ drug everolimus (Afinitor) for use in patients with pNET as well. Sutent and Afinitor are the first drugs to be approved for the treatment of pNET in over 30 years. The FDA’s decision to approve Sutent was based on a phase 3 clinical trial conducted by Pfizer that showed a six month survival advantage for patients that took Sutent as compared to those patient that did not. In the study, 171 patients with pNET were randomly selected to take Sutent or a placebo. Patients that took Sutent survived without the spread of their cancer for a median amount of time of 11.4 months, compared to only 5.5 months for the patients taking placebo. In addition, it was found that patients taking Sutent had a 71.3% probability of being alive and free of the cancer at six months compared to only a 42.3% probability for those patients taking placebo. The study was stopped early because the patients taking Sutent were doing much better than the patients taking the placebo medication. After stopping the clinical trial, the patients that were taking the placebo medication were offered Sutent for the treatment of their pancreatic neuroendocrine cancer. The survival and overall prognosis for patients with pNET has not changed much over the last 30 years because no new chemotherapeutic drugs had previously been approved for treatment. Sutent has already received approval for the treatment of pNET in Europe and other countries throughout the world. These new developments will hopefully change the outlook for Steve Jobs and other patients with the disease.
Photograph Credit: Kimberly White/Reuters