February 2008

Another 'smart' cancer drug shown to have toxic effects on the heart

Another FDA‑approved targeted cancer drug, sunitinib (marketed under the name Sutent by Pfizer), may be associated with cardiac toxicity, according to a report in the December 15, 2007, issue of The Lancet.

Sunitinib is one of several new "smart" cancer drugs called tyrosine kinase inhibitors that targets specific signaling molecules inside cancer cells that aid cancer spread. Another "targeted" cancer therapy, imatinib (Gleevec, Novartis Pharmaceuticals), was reported last year in Nature Medicine to be associated with heart failure in patients with chronic myelogenous leukemia.

Sunitinib was originally thought to be relatively free of cardiac side effects. However, a new retrospective analysis, focused on cardiovascular events, revealed a risk for heart failure, myocardial infarction and hypertension in 75 adult patients with imatinib‑resistant, gastrointestinal stromal tumor (GIST) receiving multiple cycles of sunitinib in a phase I/II trial at Dana‑Farber.

Of the 75, six (8 percent) developed symptoms consistent with moderate‑to‑severe congestive heart failure, and two had heart attacks. In all, eight (11 percent) had some kind of cardiovascular event while receiving sunitinib at FDA‑approved or lower doses. In addition, 47 percent (35 of 75) developed hypertension.

SOURCE: Children's Hospital Boston, Dec. 13, 2007