Clinical trials: the basics

Four types of clinical trials

Fred Hutchinson researchers conduct all four types of clinical trials:

• Treatment trials test new patient treatments. Such trials test new procedures or drugs to treat cancer.
• Prevention trials test new approaches, such as exercise, diet, medicines, vitamins, minerals or other supplements that doctors believe may lower the risk of a certain type of cancer.
• Screening trials test the best way to find cancer. Detection and diagnosis of cancer in its early stages give patients the best chances of survival.
• Quality-of-life trials, also called supportive-care trials, explore ways to improve comfort and quality of life for cancer patients.

Three phases of clinical trials

After they show promising results in laboratory and animal studies, new treatments or drugs are tested in an orderly series of steps, called phases. This allows researchers to ask and answer questions in a way that results in reliable information and protects patients. Clinical trials usually are classified into one of three phases:

• Phase I: These first studies in people evaluate how a new drug or therapy should be given (by mouth, injection into the blood or injection into the muscle), how often, and what dose is safe. A phase I trial usually enrolls a small number of patients, sometimes as few as a dozen.
• Phase II: A phase II trial usually focuses on one type of cancer, continuing to test the safety of treatment and beginning to evaluate how well it works.
• Phase III: These studies test a new drug, a new combination of drugs or a new therapy in comparison to the current standard. A participant will usually be assigned to the standard group or the new group at random (called randomization). Phase III trials often enroll large numbers of people and may be conducted at many doctors' offices, clinics and cancer centers nationwide.

Institutional review boards play key role in trial safety

Doctors and nurses play an important role in ensuring the safety of clinical trials.

So do financial advisers, homemakers, rabbis and many others with diverse careers and backgrounds.

Non-scientists who represent a diverse patient population are vital members of institutional review boards (IRBs), the federally mandated committees that oversee all new and ongoing research that involves human subjects.

"Community members on our IRB play a critical role in ensuring that research protocols and informed consent documents can be easily interpreted by patients," said Karen Hansen, director of Fred Hutchinson's Institutional Review Office.

"Along with the doctors, researchers and nurses, community members make active contributions to IRB deliberations as full voting members of the board."

IRB members volunteer their time, typically reviewing about 20 topics at monthly meetings that frequently last several hours.

Jim Mirel, a rabbi in Bellevue who has taught courses on medical ethics, joined one of the center's two IRBs in the fall of 2000. "We bring the perspective of the patient,' he said.

"We help provide the necessary outside objective scrutiny of human-subjects research. I know it's federally mandated, but the formality of it impressed me."

Deborah Juarez, a financial advisor frem Seattle, said that her respect for the patients who participate in clinical trials motivates her to serve as an IRB member.

"It's very clear our role is to act as a lay person, someone who can read and understand the documents," she said. "I try to ask myself, under what conditions will a patient be reading this? If I were in that position, how would I respond?"