Preliminary Drug Trials for Cancer Underreported
This lack of reporting can delay drug development, study says
MONDAY, Aug. 22, 2005 (HealthDayNews) -- The results of many phase I trials of new cancer drugs never get published in peer-reviewed journals. And many that are reported are published long after the trial is over, keeping potentially lifesaving information from reaching researchers and patients, a new study contends.
The study authors say it's important not only to do such trials, but it is incumbent upon researchers to publish the results, making them available to those doing similar research and to doctors treating patients.
Phase I trials are first human trials of new drugs or new drug combinations. These trials are usually small studies designed to test the safety of doses and the toxicity of the treatment being studied. Generally, it is not the purpose of phase I trials to study whether a drug or drug combination actually works.
The study findings appear in the Aug. 22 online edition of the journal Cancer.
"The number of phase I cancer studies done in the United States has increased dramatically," said lead author Dr. Luis H. Camacho, assistant professor of cancer medicine at the University of Texas M. D. Anderson Cancer Center, in Houston.
To determine the number of phase I cancer drug trials, the researchers looked at the number of trials submitted to the American Society of Clinical Oncology for presentation at its annual meeting in 1997. They also searched for how many of these trials had been published in medical journals.
"Seven and one-half years after being presented at a medical meeting, 67 percent of the studies have been published, but only 12 percent are published one year after being presented. That's not acceptable," Camacho said.
In another step, Camacho's team sent questionnaires to researchers asking what had happened to the data from their phase I trial and why it hadn't been published. "The top two reasons for not publishing were lack of time and author relocation" [to a new position]," he said.
Lack of time is an unacceptable reason not to publish, Camacho said. "We apply for grants. We apply for trials. Once we finish them, we present them at medical meetings, but that is not the end of our commitment. Our commitment should be to publish them."
Not publishing the results of these trials means the medical literature does not reflect the latest research, Camacho said.
"That may make an impact on patient care," he said. "Even though this is a very early stage of development, phase I results can be used to treat patients right away. You see people at cancer institutions treating patients with phase I abstracts from a meeting."
Camacho also believes phase I results must be published to keep other researchers informed of developments in the field. "If you don't report these findings, then the whole drug-development process is delayed."
Phase I trials should also take into account the efficacy of the treatment being tested, Camacho said. "The bottom line is if you do not show any efficacy in a phase I study, your chances of moving that forward to phase II are minimal," he said.
A study published in March in the New England Journal of Medicine, supports Camacho's position. In that study, researchers found that twice as many cancer patients testing medications in phase I clinical trials had positive response rates than had been previously believed.
"Phase I studies now are safer than ever," Camacho said. "Response rates can go up to 15 percent. It's more than hope. Patients have a good chance of a response in a phase I study."
Dr. Harold Burstein, an assistant professor of medicine at Harvard Medical School and the Dana Farber Cancer Center in Boston, agrees with Camacho that the results of phase I trials should be published.
"The authors make a good point in underscoring the need to publish full and final analyses from all clinical studies, including phase I trials," he said.
However, Burstein noted that not publishing phase I results is ingrained in the culture of research.
"It is well established that many reports that appear in abstract form [at meetings] do not eventually see formal publication," he said. "It is also not surprising that abstracts not selected for presentation are less likely to be published -- remember they were not chosen for presentation because they were considered to be of less inherent value."
Another expert believes that the new study's findings have important implications for patient care.
"There is a response rate between 7 and 17 percent to treatment in phase I trials," said Dr. Jerome Yates, national vice president of research at the American Cancer Society. "And a third of these are not being reported. Ideally, it would be important to know the results of all phase I clinical trails."
The American Cancer society can tell you more about clinical trials.