How Clinical Trials Work

Who sponsors a clinical trial?

Clinical trial sponsors are responsible for managing and financing the clinical trial, but not in conducting the research. A clinical trial sponsor can be an individual, an institution, a company or a government agency.

What is a clinical trial protocol?

The plan that outlines the clinical trial process is called the clinical trial protocol. The protocol will include:

  • The goal of the study and background information.
  • Inclusion and exclusion criteria for people to participate in the study.
  • Treatments, tests and procedures included in the trial.
  • Information on how long the trial will last.
  • Patient information and samples that will be collected.

 What is an Institutional Review Board?

Most clinical research studies and clinical trials in the U.S. are approved and monitored by an independent committee of physicians, statisticians and community members called an Institutional Review Board (IRB). This committee reviews the research protocol and monitors the progress of the study to protect the rights and safety of the participants.

What is informed consent?

Before enrolling in a clinical trial, you will be given an informed consent document to sign. This document describes details about the study, tests or procedures that will be done, how long the study will last, the potential risks and benefits, and who to contact during the study with any questions. After reading through the clinical trial details, you will sign the informed consent form if you want to participate in the study. Participation in a clinical trial is voluntary and you can leave the study at any time.

What do the terms placebo, randomized, and blinded mean?

  • Placebo – In order to determine whether a new treatment will be effective, certain clinical trials will include a placebo in the study protocol. A placebo is a product that resembles the drug that is being investigated but is an inactive product. For these placebo-controlled studies, you may be assigned to receive a placebo instead of the drug being tested. Comparing a new drug to a placebo can be the quickest and most accurate way to determine if the investigative treatment will be effective. Placebos will not be used in a study if it will put patients at risk. You will be told ahead of time whether a placebo will be used for the clinical trial.
  • Randomized – In a randomized clinical trial, patients are assigned to a specific treatment by chance rather than choice to avoid bias. The effectiveness of each treatment is compared during interim points during the study and if one treatment appears to be better, the trial is stopped so that the study participants can receive the more beneficial treatment.
  • Blinded – Blinded studies are clinical trials designed to prevent participants and the research team from knowing which specific treatment or placebo is being given to a specific group of patients. In a single-blinded study, the research team will know which treatment a group of participants will receive but participants will not know. In a double-blinded study, neither the research team nor the participants know which group is receiving which treatment until the study is completed. If medically necessary, however, it will be possible to find out which treatment you are receiving.

What happens after the trial is completed?

After a clinical trial is completed, the researchers analyze and interpret the results. For Phase I and Phase II clinical trials, researchers determine whether the exploratory treatment was safe and effective and decide whether to continue to the next phase or to stop evaluating the therapy. After a Phase III study, researchers determine whether the trail results indicate the treatment will be medically beneficial, often in comparison to other available treatments. If so, researchers will submit the results to the FDA for consideration for approval. If approved by the FDA, the treatment will then be available to the public and may become a new standard of care.

Results from clinical trials are often published in peer-reviewed scientific journals. The study may also be presented at a scientific or medical conference or be highlighted in the news. Published journal articles can be searched on the National Library of Medicine’s PubMed database through the study’s name, protocol identifier number, or name of one of the study research scientists or clinicians.

How to participate in a clinical trial

Do you want to participate in a clinical trial? Learn what you need to know, how to find a pulmonary hypertension clinical trial and the questions you should ask before you enroll.

Learn More