Why Don’t I Qualify for a Clinical Trial?

Clinical trials follow a strictly regulated process approved and monitored by the FDA before you ever see an investigational treatment on the market. Each trial has set and defined participant criteria to protect volunteers, and each clinical trials requires a variety of volunteers. If you’ve applied for a clinical trial and been turned away, you should know it’s OK not to qualify. There are several reasons you may not be eligible, the most important of which is for your own health and safety.


To understand more about participant criteria, we need to review the phases of clinical trials and what each one is looking for volunteer-wise. There are 4 phases of clinical research:

  • Phase 1– This phase has very few people as it is the first time the treatment is being tested in humans. Healthy volunteers help establish how the medication is metabolized and excreted in the body, and side effects are also studied.
  • Phase 2– The main goal of this phase is to measure the effectiveness of the treatment. Healthy volunteers, along with those with a specific condition or disease, will be compared to those taking a placebo.
  • Phase 3– Safety and efficacy of the treatment continue to be studied in different volunteer populations and in conjunction with other treatments.
  • Phase 4– At this point, the FDA has already approved the treatment and has made it available to the public. This phase is a requirement that continues to study the safety and effectiveness as the medication or device while out on the open market. Any side effects will continue to be monitored, and action is taken if needed.

Keeping you SAFE

The participant criteria lists which volunteers can be included, and which should be excluded. These vary by both individual studies, and the phase the study is in. As each phase concludes, the criteria is modified to account for research developments. The inclusion part of the criteria applies to those who would benefit from the study treatment. Some examples of these include age, gender, and stage of illness. Exclusion criteria lists who cannot volunteer for the study. Examples include medications being taken that may affect treatment and certain pre-existing conditions.

The criteria are meant to shield volunteers from avoidable risks. If we knew a snake was hiding under a blanket, it’d be our responsibility to tell you to prevent a bite. With clinical trials, there may be a hidden risk that you need to be protected from. Your safety is the top priority for all involved in research studies, which is why there are participant criteria guidelines.

Don’t be discouraged if you don’t qualify for a clinical trial. It just means you weren’t a good fit for that trial, not all trials. Knowing that these guidelines are in place to keep you safe should make you feel even better about volunteering. If you are interested in hearing more about our enrolling clinical trials, click here. Qualified participants receive compensation for time and travel.