Doctors reported yesterday that a new drug designed to block the growth of blood vessels in tumors improved the survival of patients with advanced colorectal cancer by 50 percent, a dramatic finding that could rapidly change the way the second-leading cause of cancer deaths in the United States is treated.
Another study, unveiled at the same cancer meeting in Chicago as the first, revealed that Erbitux, the much-maligned cancer drug at the center of a swirl of insider stock-trading investigations involving Martha Stewart and others, offered notable benefits for some colorectal patients in whom other treatments had failed. The drug also benefited lung-cancer patients in preliminary research, and it now appears likely to win eventual approval from the Food and Drug Administration.
Doctors said the findings herald the dawn of an era when cancer treatments designed on the basis of detailed genetic knowledge will begin to have a significant impact on the four types of cancer that kill the most people -- those of the lung, breast, colon and prostate.
Participants said the Chicago meeting, of the American Society of Clinical Oncology, buzzed with excitement this weekend as doctors realized the implications of the findings.
The single most compelling report came from researchers studying Avastin, a drug created by Genentech Inc., the company whose founding in 1976 launched the U.S. biotechnology industry.
The study is the first large-scale confirmation of a hypothesis pushed since the early 1970s by Judah Folkman, a Harvard University researcher who noted tumors seem to have the ability to make new blood vessels grow to supply them with nutrients. Block that ability, he reasoned, and tumor growth could be slowed or stopped.
That seems to be exactly what happened in many patients with advanced colorectal cancer who were treated with Avastin plus regular chemotherapy. The drug is an artificial antibody, a type of protein, designed to block the action of a substance that some tumors use to induce blood-vessel formation.
The Avastin study, involving more than 800 patients, was designed from the outset to meet the gold standard of cancer research: It tested not just whether tumors shrank, as most cancer studies do, but whether patients receiving Avastin as part of their initial treatment regimen lived longer.
Data released yesterday on another drug, Erbitux, suggest it might have a role to play. The drug was developed by ImClone Systems Inc. of New York. That company conducted poor studies and ran into serious problems at the FDA 18 months ago.
ImClone was caught up in turmoil after its then-chief executive, Samuel Waksal, was accused of insider stock trading for advising family members to dump shares just ahead of the bad news. He has pleaded guilty to multiple crimes, and investigations continue, including one of style maven Martha Stewart, a friend of Waksal's who dumped shares at the same time as Waksal's relatives.
Several new studies released over the weekend suggested Erbitux is likely to be a useful cancer drug. The most significant study, in colorectal-cancer patients for whom other treatments have failed, was conducted not by ImClone but by its European partner, Merck KGaA of Darmstadt, Germany, which is unrelated to the American drug company of the same name. More than half the patients in the study, who were on the verge of death when it started, saw their tumors stabilize or shrink if they received Erbitux plus a standard drug, compared to a third of patients who received the standard drug alone.
Erbitux is designed to suppress a growth factor that may help some tumors develop resistance to standard chemotherapy. One of the questions doctors now need to work out is whether Avastin and Erbitux can be used together to provide greater benefits.
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