Improving Enrollment for Prostate Cancer Clinical Trials

Patients who participate in oncology clinical trials have better outcomes than nonparticipants, and the results of such trials are ultimately used to guide treatment for all patients with cancer. Yet, fewer than 10% of patients with cancer currently participate in clinical trials. Several barriers to participation exist, with a major one being that oncologists are not offering patients the option to enroll in clinical trials.

Catherine H. Marshall, MD, MPH, Assistant Professor of Oncology at The Johns Hopkins School of Medicine, Baltimore, Maryland, shared some information focused on increasing enrollment in prostate cancer clinical trials that may be considered for patients.

What types of clinical trials are available for men with prostate cancer?

Dr Cathy Marshall: All types. Some patients are not referred for clinical trials until the treating oncologist has exhausted all available standard therapies approved by the US Food and Drug Administration. However, trials are being conducted at all stages of disease. Prostate cancer clinical trials can be considered even when there are many lines of therapies available to a patient.

Another consideration is the different phases of trials.

Phase 1 clinical trials are those where therapeutics are in early stages. These trials can be conducted when a treatment is being used for the first time in humans, so there may be little or no prior experience using the drug in humans. The main goals of these trials are determining safety and finding the right dose of a medication. Some of the trials may be specific to men with prostate cancer, but many are for patients with a variety of tumor types.

The important piece that I share with patients about these trials is that efficacy of the drug is not being tested in this early phase. These trials tend not to be randomized. However, it is important to note that although many of these drugs do not end up moving on to later-phase clinical trials, every drug we use today started in phase 1.

Phase 2 clinical trials are when efficacy is being tested. Some of these are randomized trials, and others are still single-arm trials in which all participants receive the experimental treatment. There usually are some published preliminary data available about the drug being tested, and some safety information is known about the drug.

Phase 3 clinical trials are usually randomized, or at least comparative, trials. This means some patients may end up not being assigned to a group that is given the experimental treatment.

At what point should patients be offered the option to enroll in a clinical trial?

Dr Cathy Marshall: Whenever there is a trial for which the patient might be eligible! A common time for referral is when patients are considering a new line of therapy. For example, we currently have a trial open for men with biochemically relapsed prostate cancer. It is a randomized trial of a diet and exercise intervention for men who are overweight or obese (Participation is an option for men who are not going to be started on treatment right now.

There are other types of trials, such as trials of novel imaging techniques or ones that address that also might be of interest to patients and clinicians.

How can clinicians learn what clinical trials are available to patients in their region?

Dr Cathy Marshall: First, find out what practices have clinical trials available. Many academic medical centers will have them. However, those certainly are not the only sites with clinical trials; many other clinical settings have them available too. ClinicalTrials.gov is a good place to start. You can filter for trials based on location, phase of clinical trial, and the specific disease to find what might be right for a particular patient.

Some areas may have other resources too. For example, in what is called the Washington Metropolitan DMV area (Washington, DC, Maryland, and Virginia), we have the Genito-Urinary Multidisciplinary D.C. Regional Oncology Project (GUMDROP).  The GUMDROP network is an organization that aims to increase awareness of clinical trials and can help match patients in the area to trials that are open for enrollment.

There are many challenges and barriers to be overcome to increase patient participation in prostate cancer clinical trials. Clinicians can address one of them by offering clinical trial information to patients with prostate cancer during visits when they are being evaluated for their disease. As the broader oncology community continues to try to improve care for all our patients, increasing access to cancer clinical trials is one way we can work to accomplish our goal.

Learn more about access to and disparities in prostate cancer clinical trials.