Kidney Cancer Drug Linked to Higher Rate of Heart Problems
Wednesday, February 13, 2008; 12:00 AM
WEDNESDAY, Feb. 13 (HealthDay News) -- A greater percentage of patients than previously thought may develop heart failure when taking the breakthrough cancer drug Sutent, researchers report.
The drug was approved for advanced kidney cancer and a rare form of gastrointestinal cancer.
"Our data support a role for routine cardiac monitoring for patients receiving sunitinib [Sutent] and careful study of adverse cardiac events in future studies," said study author Dr. Melinda Telli, a postdoctoral fellow in medical oncology at Stanford University School of Medicine. "This is especially important, because sunitinib is being investigated in over 30 different tumor types for advanced as well as early forms of cancer. Determining what factors put patients at increased risk will allow us to administer this medication more safely for patients whose benefits clearly outweigh the risks."
Telli was to present the findings at the 2008 Genitourinary Cancers Symposium in San Francisco. She spoke to reporters at a Tuesday teleconference.
Other experts agreed that monitoring of patients on Sutent is advisable, but they also cautioned that there is still little reason for alarm.
"This is a small study and one that makes us want to look further into it . . . but this is not a crystal clear characterization of injury," said Dr. Patrick Lowry, an assistant professor of surgery at Texas A&M Health Science Center College of Medicine and section head of laparoscopy and endourology at Scott & White Memorial Hospital in Temple.
"At the same time, this certainly is more patients with heart failure than they saw with the initial studies," Lowry said. "Perhaps, as they suggested, we need to follow patients a little bit closer from a cardiac standpoint."
And, Lowry pointed out, patients being treated with Sutent often have incurable metastatic cancer. At that point, "we're just trying to improve and extend their life as long as we can, and there are going to be pluses and minuses to anything," he said.
The study -- which was funded by Sutent's maker, Pfizer -- looked at 48 patients in a "real-world" setting who were taking the drug for either advanced kidney cancer or a gastrointestinal stromal tumor (GIST).
Fifteen percent of the patients experienced heart conditions such as symptomatic left ventricular dysfunction or heart failure while taking Sutent. The problems began between 22 days and 435 days after beginning therapy, although most started within the first three months of treatment.
The 15 percent incidence of heart trouble shown in this setting is almost double that seen in clinical trials, which had found that up to 8 percent of patients had experienced heart failure.
Heart failure involves a decline in the heart's ability to pump blood.