Drug maker Pfizer Inc. said Thursday it ended a successful late-stage clinical trial of its cancer drug Sutent early after data showed the drug showed significant benefit for patients with a rare form of pancreatic cancer.

The company in a news release said the phase 3 trial included patients with advanced pancreatic islet cell tumors, also known as pancreatic neuroendocrine tumors. Their drug Sutent in the trial showed significant improvement in extending the time patients survived and their disease did not spread, compared to a combination of standard treatment and a placebo.

The results sent Pfizer shares up $1.23, nearly 10% to $14.02. The stock had lost about a quarter of its value since Jan. 26, when Pfizer agreed to buy smaller rival Wyeth for $68 billion.

An independent Data Monitoring Committee recommended halting the test after concluding that Sutent (sunitinib malate) showed greater "progression-free survival" than a placebo, the company said. All trial participants will have the choice of continuing treatment with Sutent or switching from a placebo to the drug.

Dr. Mace Rothenberg, Pfizer's senior vice president of medical development and clinical affairs, in the release said, "These and previously reported phase 2 data contribute to the growing body of evidence indicating activity with sunitinib in patients with pancreatic islet cell tumors."

The news release said complete data from the trial is being "analyzed and more details will be presented at an upcoming scientific meeting." Details on the duration of survival benefit for those using Sutent have not yet been released.

The U.S. Food and Drug Administration have already approved Sutent for the treatment of certain kidney and stomach cancers.  Pfizer hopes to have the drug approved as a treatment for advanced tumors in the islet cells of the pancreas.

Pfizer said pancreatic islet cell tumors are rare malignancies of the pancreas, with an incidence of five million to 10 per million worldwide annually. The company described the cancer as rare, with limited options for treatment.

Sutent, an oral drug that is designed to block molecules that help cancers grow and spread throughout the body and is already the company's best-selling cancer drug, with $847 million in sales in 2008, including $254 million in the U.S.

The drug Sutent raked up some controversy after recent studies suggested it might boost patients' blood pressure and increase their risk for heart failure. Pfizer issued a statement in December, to say that these cardiovascular risks "were medically manageable in most patients and underscore the importance of having a collaborative team of health-care professionals working together to appropriately manage patients who have limited available options" in treating their cancer.