Trial and Error


Patients Weigh Benefits, Risks of Participating in Clinical Trials

If you read headlines about medicine and science, you’ll see sentences like these a lot: “New lung cancer drug starts Phase II clinical trial.” “Array BioPharma reports results in two Phase I clinical trials.”

Every time you read the words “clinical trial” — be it Phase I, II or III — there are dozens of real people, some healthy volunteers and some patients with an illness, who participated in that trial to make it possible. In some cases, clinical trials compare two existing therapies head-to-head to see which is better, but often, participants in a clinical trial are trying a new medication about which little may be known.

Without clinical trials, new medications can’t be developed or approved., the U.S. government’s Web site for keeping track of these trials, currently lists more than 75,000 trials with locations in 169 countries. More than 20 million people in the United States are currently enrolled in clinical trials.

That sounds like a lot — but when you consider how many people have serious illnesses, such as Parkinson’s or Alzheimer’s disease, or cancer, it’s less than you might expect. In fact, it’s estimated that less than 1 percent of the 1 million people with Parkinson’s disease currently participate in trials, and less than 2 percent of all people with cancer participate. The National Cancer Institute has projected that if 2 percent or 3 percent more people would participate, studies could be completed in two years instead of three.

Why don’t more patients participate in clinical trials? For some, it’s simply lack of information. A 2005 Harris Interactive survey found that 80 percent of people with Parkinson’s disease would participate in a clinical trial if one were available in their area, but only 11 percent had been told about clinical trials by their doctors.

Another key barrier for many patients is the fear of side effects from an unknown drug. Many also worry that they will be “randomized” (assigned) into the less-effective arm of a clinical trial — for example, if they think a new experimental medication might be better for their disease, they don’t want to get assigned to the older comparative therapy.

There’s also an understandable public skepticism about the realities of clinical trials. In a new book, “Chasing Medical Miracles: The Promise and Perils of Clinical Trials,” journalist Alex O’Meara chronicles his experience with a clinical trial to “cure” his type 1 diabetes through the transplantation of islet stem cells. (The therapy worked for a year but ultimately failed.)

As O’Meara’s book notes, clinical trials are a billion dollar industry, and there’s money to be made. Sponsors of clinical trials can pick and choose which results they release — of 74 clinical trials for 12 antidepressants, for instance, 94 percent of those that yielded positive results were published, while only 14 percent of the unfavorable results (usually called “negative trials”) were released.

Yet clinical trials have enormous benefits. Without them, we would not have Herceptin, the drug that reduces breast cancer recurrence by more than 50 percent and cuts mortality by one-third in patients with a certain subtype of cancer. We would not have Gleevec, which keeps many patients with chronic myeloid leukemia in remission.

Clinical trials also sometimes benefit the individual patient. If you have access to an experimental treatment that’s only available as part of a clinical trial, and that medication turns out to have a substantial benefit in the treatment of your disease, you’re in luck. But that’s just what it is — luck. A whopping 95 percent of all drugs that pass Phase I testing are eventually rejected as not effective enough or too toxic, so the odds that you will get access to some kind of “miracle drug” are slim. You might also find yourself assigned to the control group, taking the currently approved “standard of care” medication rather than the new experimental therapy.

Then why participate in a clinical trial? Most patients who volunteer say that it’s not just for themselves, but for the people who come after them. A survey published in the Archives of Internal Medicine in 2008, which interviewed patients from an HIV therapy trial in Argentina, Brazil and Thailand, found that 90 percent believed they were making an important contribution to society, and 84 percent expressed pride in helping to advance scientific knowledge.

Ultimately, the decision to volunteer for a clinical trial — or not to — is a complex and personal one. Only you know if the potential benefits to society and to you are worth the risks you’ll take and the additional inconvenience you may have to experience. Many people say they are. O’Meara, despite his jaded take on the clinical trial industry as a whole, is glad he participated in his islet-transplantation trial. “The study was important,” he writes. “If not for me, then for someone else.”

“Volunteering for a trial to help others and advance medical science is honorable. Many people feel compelled to ‘give back’ or to sign up for a trial exploring new treatments and drugs for a condition a family member or loved one suffers from,” O’Meara said. “If such an option feels like something you want to do, then by all means consider it.”

About the Author

Gina Shaw is the medical writer for The Washington Diplomat.