People with advanced cancers who try experimental treatments (search) are helped more than previously thought, according to the most comprehensive look at government-sponsored tests over a decade.
These are patients who haven't benefited from other therapies and have few options left. But testing new treatments on them has been criticized by some who feel the patients are given false hope since previous reviews showed they only worked in about 4 percent to 6 percent.
However, this latest and largest study found that about 11 percent were helped by experimental treatment, and in some cases as many as 27 percent were better off.
"The numbers aren't as bleak as they sometimes are portrayed," said one of the researchers, Christine Grady, of the National Institutes of Health's Department of Clinical Bioethics (search). "But the numbers don't tell the whole story."
She said their review covered tests on different types of drugs and vaccines, combinations of drugs and some that had already been approved by the Food and Drug Administration. Only 22 percent of the reviewed tests were for a single chemotherapy drug; that was the only kind included in the reviews that showed low overall response.
She said patients who want to volunteer for early drug testing should look at the details for the type of experiment they are considering.
"Phase I trials are not all alike," she said.
The first phase of drug testing in people is primarily designed to see if the treatment is safe and to find the right dose for future tests, though doctors also hope to get some idea of whether it works. These early tests are done in cancer patients who have failed other treatments.
Grady and her colleagues analyzed 460 tests with 11,935 participants, including some previously unpublished tests. They were done between 1991 and 2002 and were paid for by the NIH's National Cancer Institute. Their review did not include tests financed by drug makers or those done on children. The research appears in Thursday's New England Journal of Medicine.
Overall, about 3 percent saw their cancers disappear and about 8 percent had a substantial shrinkage of their tumors. Additionally, 34 percent saw some tumor shrinkage or saw their disease stabilized.
The rate of deaths blamed on the treatments stayed the same, about half a percent. Side effect information was only available for about a third of participants; about 14 percent had at least one serious side effect.
In tests for a single chemotherapy drug, the overall response rate was about 5 percent, similar to rates in previous reviews. The highest response rates were in tests that combined approved drugs with experimental ones or tested doses of approved drugs.
"It does lend support to the statement we frequently make: If you're a candidate for a clinical trial, it's almost always the smartest thing you can do," said Dr. Larry Norton, deputy physician-in-chief at New York's Memorial Sloan-Kettering Cancer Center.
He said cancer patients need and want more access to such tests.
"People really desperately want to receive therapy that stands any chance of benefiting them, and of benefiting humanity in general," he said.
Two of the most well-known early cancer experiments illustrate their promise and pitfalls.
In 1999, about 1,700 desperate patients sought 25 slots in a Boston study testing endostatin (search), an experimental drug that attacked tumors in an entirely new way, by starving their blood supply. The widely touted treatment proved wildly disappointing.
The opposite happened with Gleevec, one of a new generation of genetically designed, targeted cancer treatments that has become a wonder drug for people with certain types of leukemia. Many of those who got the drug in early experiments sponsored by its maker are still alive and doing well on it.
Dr. Razelle Kurzrock, director of the Phase I program at the University of Texas M.D. Anderson Cancer Center in Houston, said the NIH review supports her conviction that patients can benefit from early phase testing. She said patients say their quality of life is improved just by "not giving up."
"Patients should be reassured and physicians who are referring patients should not feel that this is an ethical dilemma," said Kurzrock, co-author of an accompanying editorial in the journal.