The Importance and Role of Cancer Clinical Trials

Only three percent of U.S. adults with cancer (all cancer types) participate in clinical trials, but it is estimated that 20 percent are eligible.

There are valid reasons why people do not participate. For example, the patient may not meet the eligibility criteria or there may be practical or personal obstacles such as the distance to the closest trial. Unfortunately, some women do not participate because they don’t have the information they need or are given the wrong information. It is important that each person has the correct information to make an informed decision. Women should be able to consider clinical trials from the start of their care.

Clinical trials are the paths to create and test treatments that are more effective and less toxic. New treatments are tested in a series of trials known as Phase I, Phase II, and Phase III. The Federal Drug Administration (FDA) checks and approves new cancer drugs and other treatments. But they only do that after the final, Phase III, trials have shown better results or less side effects compared to standard treatments. Likewise, new ways to do surgery are recommended after Phase III trials. Results must show that they new methods are more safe, tolerable, or effective.

The Role of Preclinical Testing

Preclinical testing does a complete check of a drug before it is part of a Phase I trial. Usually this is done in a series of experiments on cancer cells in test tubes and then in mice or other animals. Experts learn how best to prepare and store the drug and about dose.

The Role of Phase I Trials

Phase I trials are the first trials when a new drug or treatment is used in humans. The goal for these trials is to learn the best dosing schedule. These are the main things tested for the dosing schedule.

Amount of the drug
How the drug is given (such as by mouth or into a vein)
How often the drug is given

Researchers focus on learning about the drug or its side effects as well as any toxic or harmful effects.

Phase I drugs have a limited track record of how well they do against cancer. So, they are usually only open to people who have not responded to more established treatments. Usually between 15 and 50 people take part in a Phase I trial.

Positive results to the treatment are hoped for and noted. But, the true evaluation of the drug awaits the Phase II trial.

The Role of Phase II Trials

Phase II trials test whether a new drug or treatment works against a specific type of tumor. For instance, a trial isn’t just for ovarian cancer, but specifically for epithelial ovarian cancer.

Usually 14 to 40 patients are part of a Phase II trial. They don’t all join the trial at once. If the first group fails to respond to the treatment, the trial is usually closed. But, if some of the first 14 to 21 patients have good results, the trial is often expanded. Then the goal is to help learn the percentage of people who will respond to the treatment as well as learn the side effects and toxicities.

For the new drug or treatment to have more testing, researchers usually require that at least one out of five patients show a response.

The Role of Phase III Trials

Phase III trials are the largest and most important of the clinical trials. Several hundred to a few thousand patients are needed for most of these trials. Their purpose is to learn whether a new treatment can improve outcomes when compared to an already proven treatment. Patients may take only the new treatment or make take it with another treatment.

It helps to know some of the terms used in these trials.

The people in the trial who take the new treatment are called the experimental arm of the trial.
The people in the trial who take the already proven treatment are said to be in the control arm of the trial.
The proven treatment is often called the standard treatment.

The goal of the new treatment is often to learn whether patients live longer or have longer remissions with it compared to the standard treatment. While it is the desire and hope that new treatments in Phase III trials will produce a better outcome, such is not always the case. Sometimes the outcome is no better and the toxicities are worse. However, virtually all of the celebrated standard treatments offered today were discovered through clinical trials done in past years.

How the Quality of Clinical Trials Is Monitored

Clinical trials in cancer are supported and done by these groups.

Organizations
Comprehensive cancer centers
Government agencies and federally funded programs
Industry, including the pharmaceutical industry
Foundations
Privately funded groups

There are about 10 major cooperative groups in the United States and Canada. About 50% of patients enrolled in cancer clinical trials come through these groups. The Gynecologic Oncology Group (GOG) develops and supports many of the gynecologic cancer trials in the United States. The GOG has been steadily advancing gynecologic cancer understanding and outcomes for the past 35 years.

Most large teaching hospitals take part in clinical trials. But trials are also available at many community hospitals, outpatient clinics, and physicians’ offices.

The design of each trial must pass multiple levels of approval. Both scientific and ethical issues are checked. These are some of the main groups doing the monitoring.

Institutional Review Boards (IRB) are part of every medical institution. The board’s role is to review each clinical trial for these things.

To make sure that the risks and benefits to the patients who take part are reasonably balanced
To make sure that each patient in the trial has given their informed consent

An independent safety committee keeps tabs on the trial as it’s running. This group usually includes a non-medical community member. One thing they look for are strong early signs that either of the treatments is better or worse in how well it works. If so, the trial is closed. The same is true if the new treatment is too toxic. Researchers never knowingly subject a patient to inferior treatment or unnecessary toxicity.

Not all clinical trials are about the effectiveness of drugs or other treatments. Previous and current trials lead by the Gynecologic Oncology Group help researchers learn more about the biology of tumors or better ways to prevent cancer. This information also helps improve the design of new treatments.

Clinical trials should not be thought of as “last resort” treatments. In fact, patients in clinical trials are often the first to take the treatments of tomorrow, the cutting edge of care. A person’s participation in a clinical trial adds to our understanding of a certain cancer. Today’s improved cancer survival is based on all that was learned through previous trials.

Source: 2006 State of the State of Gynecologic Cancers: 4th Annual Report to the Women of America, by the Gynecologic Cancer Foundation