TUESDAY, Jan. 17 (HealthDay News) -- The experimental cancer drug regorafenib appears to extend survival slightly in patients with metastatic colorectal cancer, a new trial indicates.

Regorafenib is a so-called multikinase inhibitor, which targets several of the ways cancer develops and grows, researchers said.

"The drug was tested on patients with metastatic colorectal cancer who had progressed after standard therapies, meaning they had no treatment options available," lead researcher Dr. Axel Grothey, a professor of oncology at the Mayo Clinic, said during a noon press conference at the Gastrointestinal Cancers Symposium in San Francisco on Tuesday.

The drug is designed to stop tumor progression, both by preventing cancer cells from growing and by preventing these cells from developing the blood vessels needed to keep them alive, the researchers explained.

In the trial, more than 700 patients with metastatic colon cancer were randomly selected to receive regorafenib or placebo.

In addition, all patients received care to treat symptoms, but not to change the course of the disease, the researchers noted.

Treatment included antibiotics to fight infections, painkillers and corticosteroids.

The investigators found that patients taking regorafenib survived an average of 6.4 months, compared with five months for those receiving a placebo -- an increase in survival of 29 percent.

In addition, 44 percent of the patients taking regorafenib responded to the drug or had their cancer slowed, compared with 15 percent of the patients receiving placebo, they reported.

Based on these findings, the trial was stopped in October so that all patients could be offered the drug.

The trial was funded by the maker of regorafenib, Bayer HealthCare Pharmaceuticals.

"The drug helped patients live longer," said Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society. "But you have to keep in mind that these patients had advanced disease."

And, the gains were modest, he added. "Patients who got the drug lived about one month longer. Unfortunately, the difference between the groups in the time it took for the disease to get worse was small -- about six days," he said.

Lichtenfeld thinks that using the drug earlier in treatment might have more impact. "But not every drug, when moved earlier in the course of the disease, is necessarily proven to be effective," he cautioned.

Grothey noted regorafenib is being tested in a phase 2 trial in patients with earlier stage colorectal cancer, in hopes that the results will be even more dramatic.

Research presented at medical meetings should be viewed as preliminary until published in a peer-reviewed medical journal.

More information

For more on colon cancer, visit the American Cancer Society.