The findings of this phase-2 clinical trial will be presented at the American Society of Clinical Oncology (ASCO) meetings in Atlanta on Sunday (June 4).
Dr. Mark A. Socinski, associate professor of medicine at the University of North Carolina at Chapel Hill and a clinical faculty member of the UNC Lineberger Comprehensive Cancer Center, is the study's principal investigator. Socinski said the activity data on Pfizer's oral drug, sunitinib malate, appears "very similar" to that of other currently approved agents for non-small cell lung cancer.
Another drug, Avastin, keeps new blood vessels from forming and has been shown to help people with advanced lung cancer live longer when it was given along with chemotherapy.
Sunitinib, which is also an anti-angiogenic agent, interferes with a tumor cell's ability to develop new blood vessels. It acts on a molecular level by inhibiting an enzyme – tyrosine kinase – that activates cellular growth factor receptors, thus preventing further blood vessel growth.
"As a single agent, this drug worked in a difficult group of patients whose advanced disease had been previously treated with other chemotherapies and whose options were limited," Socinski said.
According to the UNC thoracic oncologist, among 63 patients treated, there were six confirmed partial responses, with disease stabilized in an additional 27. He said data as to length of survival "are still pending."
The patients were enrolled in the trial from January to October 2005. Treatment involved one 50-milligram oral dose (pill) per day for four weeks followed by two weeks off treatment, thus a six-week treatment cycle.
Adverse affects (toxicities) of the drug include fatigue, nausea, vomiting, abdominal pain and high blood pressure. Two patients developed a pulmonary hemorrhage and one a cerebral hemorrhage.
After the initial 63 patients, 47 more have been treated on a continuous dose of the drug, at 37.5 milligrams per day. This extension of the clinical trial will explore the effectiveness and safety of a continuous dosing strategy, Socinski said.
Along with UNC, other centers involved in the trial were the Johns Hopkins University School of Medicine in Baltimore; Washington University School of Medicine in St. Louis; University of Pittsburgh School of Medicine; Southeastern Medical Oncology in Glassboro, N.C.; University of Virginia in Charlottesville; the University of Turin in Italy; and San Pablo Hospital and Germans Trias and Pujol Hospital in Barcelona, Spain.
According to the American Cancer Society, about 85 percent of all lung cancers are of the non-small cell type. Pfizer Inc., La Jolla, California, funded this clinical trial.
Note: From Saturday (June 3) through Monday (June 5), during the ASCO meetings, journalists seeking an interview with Socinski should contact Tom Hughes at (919) 741-8840 (cell) or tahughes@unch.unc.edu.
UNC Medicine contacts after June 5: Les Lang at (919) 843-9687 or llang@med.unc.edu; Dianne Shaw, (919) 966-7834 or dgs@med.unc.edu.