CLINICAL TRIALS

Prior to marketing a new drug or new treatment, it must be shown to be both safe and effective. Typically, this is accomplished via clinical trials - carefully controlled studies designed to test and evaluate new drugs and new treatment plans. These trials are carried out to learn more about the new treatment and to find better therapies. In the U.S., the Food and Drug Administration (FDA) regulates the process; new drugs and treatments require FDA approval.

Understanding the Clinical Trials Process

Clinical trials generally proceed in a series of steps or phases. Based on laboratory findings, current treatment method and previous trials, scientists formulate questions they would like to have answered. Then, a clinical study is carefully designed to provide answers. Each step builds on the previous one to expand knowledge about the drug or treatment program in question.

Before a company can initiate testing a new drug or treatment in humans, it must conduct extensive pre-clinical research, involving years of laboratory experiments in animal and human cells, and then testing on animals. If this stage of testing is successful, the company provides the data to the FDA, requesting approval to begin testing the drug or treatment on people. This is called an Investigational New Drug application (IND), and indicates the results of previous experiments; how, where and by whom the new studies will be conducted; the chemical structure of the compound, how it is manufacture and how it is thought to work in the body; and any toxic effects found in the animal studies.

Not all clinical trials study treatments. Many clinical trials study new ways to detect, diagnose, or determine the extent of disease. Some even look at ways to prevent the disease from happening in the first place.

Clinical testing is normally done in three phases, each successive phase involving a larger number of people. Once the FDA has granted a New Drug Approval (NDA), companies may also conduct post marketing or late phase three/phase four studies. Progress reports on clinical trials must be submitted at least annually to the FDA.

Phase I studies involve a small number of healthy volunteers (20 to 80). The study is designed to assess the drug's safety, determine what happens to the drug in the human body—how it is absorbed, metabolized, and excreted as well as the duration of its action. A phase I study will investigate side effects that occur as dosage levels are increased. This initial phase of testing typically takes several months.

Once a drug has been shown to be safe, it must be tested for effectiveness. Phase II trials involve approximately 100 to 300 volunteer patients (people with the disease) and may last from several months to two years. Most phase II studies are "randomized trials" meaning that one group of patients will receive the experimental drug, while a second "control" group will receive a standard treatment or placebo. Often these studies are "blinded"—neither the patients nor the researchers know who is getting the experimental drug. In this manner, the study can provide the company and the FDA comparative information about the relative safety of the new drug, and its effectiveness.

Large-scale testing involving 1,000 to 3,000 patients during Phase III provides the company and the FDA with a more thorough understanding of the drug's effectiveness, benefits, and the range of possible adverse reactions. Most phase III studies are randomized and blinded trials. Phase III studies typically last several years.

Once a phase III study is successfully completed, a company can request FDA approval for marketing the drug, filing a New Drug Application (NDA). The NDA contains all of the scientific information gathered during the clinical trials. Once FDA approves an NDA, the drug or treatment becomes available for physicians to prescribe. A company must continue to submit periodic reports to the FDA, including any cases of adverse reactions. In late phase III/phase IV studies, companies continue to evaluate their product, often comparing it with other drugs already in the market; monitor a drug's long-term effectiveness and impact on a patient's quality of life; and determine the cost-effectiveness of a drug therapy relative to other traditional and new therapies.

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Why Participate in Clinical Trials

Choosing to participate in a clinical trial is an important personal decision. People participate in clinical research for a variety of reasons. For some people dealing with AMD, participating in a clinical trial may offer the psychological boost of "taking charge" - taking an even more proactive approach to battling their disease. For others there is the powerful knowledge that their participation will benefit generations to come. People who volunteer for phase II and phase III trials can gain access to promising drugs long before these compounds are approved for the marketplace. They typically will get excellent care from the physicians during the course of the study. This care also may be free.

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Benefits and Risks Associated with Clinical Trials

There are both benefits and risks associated with clinical trials. By participating in a clinical trial, you can:

  • Take an active role in your own health care.
  • Gain access to new treatments that are not available to the public.
  • Obtain expert medical care at leading health care facilities during the trial.
  • Help others by contributing to medical research.
  • Clinical trials have risks:
    • There may be side effects or adverse reactions to medications or treatments.
    • The treatment may not be effective for you.
    • The protocol may require a lot of your time for trips to the study site, treatments, hospital stays, or complex dosage requirements.
    • Patients considering participating in clinical research should talk about it with their physicians and medical caregivers. They also should seek to understand the credentials and experience of the individuals and the facility involved in conducting the study.
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Questions to Ask Before Agreeing to Participate in a Clinical Trial

People should know as much as possible about the clinical trial and feel comfortable asking the members of the health care team questions about it, the care expected while in a trial, and the cost of the trial. The following questions might be helpful for the participant to discuss with the health care team.

  • What is the main purpose of the study?
  • Who is going to be in the study?
  • What kinds of tests and treatments will be used and how?
  • Where is the trial being conducted?
  • Will hospitalization be required?
  • How long will the trial last?
  • Who will be in charge of my care?
  • How will I know that the treatment is working? Will results of the trials be provided to me?
  • Why do researchers believe the new treatment being tested may be effective? Has it been tested before?
  • What are the alternative treatments besides the one being tested in the trial?
  • Who is sponsoring the trial?
  • What type of long-term follow up care is part of this study?
  • Can I opt to remain on this treatment, even after termination of the trial?
  • Are there any risks involved?
  • What are the possible benefits?
  • How might this trial affect my daily life?
  • How do the possible risks, side effects, and benefits in the study compare with my current treatment?
  • How will patient safety be monitored?
  • What happens if I am harmed by the trial?
  • Who will pay for the treatment?
  • Do I have to pay for any part of the trial?
  • Will I be reimbursed for other expenses?

For the most part, the drugs used in clinical trials are given free of charge to the study participants. However, there may be other costs associated with the trial, such as blood work, x-ray tests, and travel expenses. Health insurance may cover some of these items and some may be offered free of charge. Medicare now covers all routine patient care costs associated with clinical trials. The financial details should be discussed prior to enrolling in a trial.

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Clinical Trials Eligibility

Before you join a clinical trial, you must qualify for the study. Some research studies seek volunteers with illnesses or conditions to be studied in the clinical trial, while others need healthy volunteers. All clinical trials have eligibility guidelines about who can get into the program. Guidelines are based on such factors as age, gender, type and stage of disease, medical history, and current medical condition. Eligibility criteria help investigators target certain groups who may benefit from the new treatment and assure that the study results answer the questions posed by the investigators. Eligibility criteria also protect participants from known risks. Individuals with other medical problems such as abnormal kidney or liver functions, for instance, may not be eligible for certain drug therapies.

The factors that allow you to participate in a clinical trial are called inclusion criteria and the factors that keep you from participating are called exclusion criteria. It is important to note that inclusion and exclusion criteria are not used to reject people personally. Instead, the criteria are used to identify appropriate participants and keep them safe. The criteria help ensure that researchers will be able to answer the questions they plan to study.

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Current Clinical Trials

Clinical trials are sponsored by government agencies, such as the U.S. National Institutes of Health (NIH); pharmaceutical and biotechnology companies; individual physician-investigators; health care institutions such as health maintenance organizations (HMOs); nonprofit organizations; and organizations that develop medical devices or equipment. Trials can take place in a variety of locations, such as hospitals, universities, doctors’ offices, or community clinics.

Comprehensive and up to date information on most of the latest clinical trials is maintained by the USA government, National Library of Medicine. The data base is easy to search and free of charge to the public. www.clinicaltrials.gov/ Just enter the search term you wish, most likely either age-related macular degeneration or macular degeneration, and full trial information, including contact details will be shown.

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New study seeks to enroll 4,000 participants with AMD

The randomized study, AREDS2, sponsored by the National Eye Institute is looking for patients between the ages of 50 and 85 with AMD in both eyes, or advanced AMD in one eye. The study will build on the previous AREDS (Age-related Eye Disease Study), which concluded that taking high-dose of antioxidants and zinc can reduce the risk of progression to advanced AMD by 25% and the risk of moderate vision loss by 19%.

For more information visit: http://www.nei.nih.gov/neitrials/viewStudyWeb.aspx?id=120#Patient%20Eligibility