At least one dose interruption was reported in 30% and 12% of patients in the sunitinib and placebo groups, respectively. Adverse events were the primary reason for interruption.
"These studies provide optimism regarding the treatment of malignant pancreatic neuroendocrine tumors, because both drugs are effective at improving disease-free survival, even in patients in whom other treatments have failed, and thus offer effective therapies where there were none before," wrote Dr. Robert T. Jensen, a researcher at the Digestive Diseases Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, and Dr. Gianfranco Delle Fave, professor of gastroenterology at Sapienza University of Rome, in an accompanying editorial (N. Engl. J. Med. 2011;364:564-5).
However, a number of unanswered questions make that optimism guarded, according to the editorial. Will the improvement in disease-free survival seen with everolimus translate to improved overall survival? Will patients in this population need to continue taking these drugs for years, given that both seem primarily to stabilize disease, rather than cure it? If patients stop responding to one drug, can they be treated with the other or a combination of both? Can these drugs be used in the neoadjuvant or adjuvant setting, or in combination with other treatments?
Perhaps most importantly, it’s unclear how the side effect profiles will affect long-term adherence to treatment, particularly given that many patients have excellent quality of life with no treatment until late in the disease course.
The study was sponsored and designed by Pfizer, which makes Sutent. Data collection and statistical analyses were also performed by the company. In addition, the first draft of the article was prepared by Dr. Raymond with help from Pfizer and medical writers paid by the company. All of the study authors reported relevant financial relationships with Pfizer. Several coauthors are employed by Pfizer. Dr. Jensen and Dr. Delle Fave reported having no relevant financial relationships.