So you're interested in taking part in a clinical trial, you say -- if only someone could just answer some basic questions and reassure you about the fine points. Where do you begin your search for reliable information?
Prospective study participants often have concerns about potential benefits, personal risk, denial of treatment and eligibility, say research experts. We broached these issues with Deborah Zarin, director of ClinicalTrials.gov, a Web site set up by the federal government to be a central clearinghouse of information on private- and government-sponsored medical studies. Here, in brief, are her responses and some dependable resources for further information on joining clinical trials.
What do I stand to gain by joining a clinical trial?
Clinical trials often allow participants access to new and possibly improved treatments before they become publicly available. If the studied treatment is found to be helpful, you may be one of the first patients to benefit. And while you're contributing to science, you'll rate unusually attentive care at some of the nation's leading medical facilities.
To what extent am I putting myself at risk by taking part in a clinical trial?
That depends on the nature of the trial and who's conducting it. Enroll in a trial sponsored by the National Institutes of Health or other government-sponsored institution, and you can be assured of the tightest safety controls. Wander off the reservation, and you'll want to do more checking for safeguards.
"It would be important to know that the trial was approved by an institutional review board," (IRB) a committee of researchers, statisticians and doctors that upholds ethical guidelines, said Zarin, who spoke to us in a series of email and phone interviews.
All human trials conducted by federally funded institutions must have an IRB, as must any study seeking Food and Drug Administration (FDA) approval of a drug or medical device; most other human studies also require this oversight. It's also important, Zarin said, "to know who funds the trial and the nature of the scientific review that was conducted. For example, NIH-sponsored studies are rigorously reviewed for scientific content prior to funding." Scientific review, usually overseen by the agency or institution funding the trial, ensures that researchers have a sound and valid basis for conducting the trial. Trials listed on the federally sponsored Web sites below have already been vetted to confirm they adhere to these requirements.
For an investigational trial -- one testing an experimental drug or treatment -- consult your doctor before deciding if the trial is right for you.
"The potential risks and benefits . . . need to be evaluated with the help of your health care provider," wrote Zarin. "It is not possible to say, in general, when the risks are 'high' or 'low' because they need to be compared with the risks (and benefits) of not participating."
Adverse reactions can include "unpleasant, serious or even life-threatening side effects," such as stroke or heart attack, according to ClinicalTrials.gov, which was developed by the National Library of Medicine and the FDA. When evaluating risks, the "stakes tend to be higher when you're dealing with a more serious condition," Zarin said. Some studies require patients to forgo other types of treatments; doing so could aggravate a chronic medical problem. Health safeguards, however, are built into most studies. Data safety and monitoring boards -- "required for multi-site clinical trials involving interventions that entail potential risk to the participants" -- keep tabs on the health of participants during a trial, paying particular attention to any negative effects that the treatment may be causing, according to the National Institutes of Health (NIH). Participants with life-threatening medical conditions, such as cancer, typically receive standard treatments in addition to any experimental ones they may receive in the course of the trial.
What if I get the placebo?
It could happen. Many studies have just as many participants on placebo (a sham treatment) as on the treatment being studied. Prospective participants need to weigh this possibility before agreeing to participate. The informed-consent forms used in most studies explain patient rights and list important study details "such as [the trial's] purpose, duration, required procedures and key contacts," according to ClinicalTrials.gov.
Only rarely do those in the placebo group end up getting the real thing. That happens when a clinical trial shows such clear benefit for the treatment group that researchers cannot justify withholding therapy from any subjects.
Last year that happened with a trial involving 1,050 African Americans with heart failure after researchers found participants taking BiDil had 43 percent fewer deaths than those taking placebo. When the study was halted nine months early, 54 of the 532 patients in the placebo group had died, compared with 32 of the 518 patients in the BiDil group, according to the findings, published in November in the New England Journal of Medicine.
Sometimes -- unexpectedly -- the placebo ends up being the healthier treatment. Before the start of a large Women's Health Initiative (WHI) study of post-menopausal women receiving hormone replacement therapy, debate centered around the ethics of withholding estrogen and progestin from women in the control group, since it had long been assumed that the hormones helped prevent heart disease and hip fractures. But the study was halted early in July 2002 when women in the hormone group were found to be at increased risk for breast cancer, heart attacks, strokes and blood clots.
What might make me ineligible for a clinical trial?
While some trials seek participants with specific diseases, others seek healthy volunteers and exclude those with chronic medical problems. Other common criteria include age, sex, type and stage of disease and treatment history.
Many Web sites provide listings of trials that are searchable by medical condition, location and recruitment phase. Web sites run by government or academic entities include reliable listings and advice for locating and enrolling in clinical trials. Other information can be found on the Web sites of pharmaceutical companies and doctors' offices. These listings are largely limited to trials in which those companies or doctors are involved. Here are some options:
ClinicalTrials.gov 12,900 listings, organized by disease or condition, treatment, location, age group, study phase and sponsor; 4,500 of those trials are currently recruiting patients. Go to www.clinicaltrials.gov or call the National Library of Medicine, 888-FIND-NLM.
Eli Lilly and Co. Clinical Trial Registry Pharmaceutical company's trial listings. www.lillytrials.com.
National Cancer Institute's Clinical Trials Database Provides listings and general advice for enrolling in a cancer trial. www.nci.nih.gov/clinicaltrials.
National Eye Institute's Clinical Studies Database Search for trials involving specific eye diseases and conditions. www.nei.nih.gov/neitrials/index.aspx.
National Human Genome Research Institute's Clinical Trials Database Lists studies that aim to investigate how genes can influence or cause diseases. www.genome.gov/10004414.
National Institutes of Health's Clinical Studies Comprehensive Database Go to clinicalstudies.info.nih.gov/index.html or call 800-411-1222.
Mayo Clinic Provides advice and definitions for common clinical trial terms. www.mayoclinic.com; search for "clinical trials."
ClinicalTrials.com Owned by a Maryland-based firm that specializes in patient recruitment, the site lists several hundred trials sponsored by its clients. www.clinicaltrials.com.
Thomson CenterWatch Lists more than 41,000 trials; run by a Boston-based publishing and information services company. www.centerwatch.com.