, the online registry for clinical trials in the United States, was launched in 2000 in response to a directive from the Food and Drug Administration (FDA). This registry contains information about medical studies performed in human subjects, and is intended to be used as a resource by doctors, patients, researchers, and members of the public.

Since its inception, almost 300,000 studies have been registered on the site.

Basic Transparency Requirements

Initially, the registry was created to promote transparency by providing a publicly available list of clinical trials that had received private or federal funding to test the efficacy of drugs designed to treat serious diseases. Since its launch, however, the requirements have been expanded to require the registration of additional types of studies and more information about these studies.

Today, the registry lists almost 300,000 studies that have been or are being conducted in the United States and worldwide.


To satisfy current regulations for compliance and transparency, the following information must be included for each study registered on the site:

  • The disease or condition that the study is investigating

  • The intervention that the study is testing

  • The title of the study, as well as a description of the study design

  • The eligibility criteria (in other words, who will participate in the study)

  • Where the study is being performed and how to contact these locations

  • Links to relevant information contained in other online resources


In 2008, the results database was launched to further promote transparency in reporting clinical study results. This database contains basic results from certain types of clinical trials, and requires research groups to post results to within one year of study completion. These basic results must include the following information:

  • A participant flow (for example, how many subjects were recruited to the study and assigned to each intervention, as well as how many completed the study or dropped out)

  • Baseline characteristics of the participants (demographic data such as age and gender)

  • Outcome measures and statistical analyses showing the results and their significance

  • A list of adverse events, both expected and unexpected, including how many of the subjects were affected

 How Compliant Are Most Researchers?

The number of trials to post their clinical study results to has increased steadily since the database was launched:


However, compliance with the transparency requirements varies widely. For example, a study published in BMJ found that less than 50% of trials listed in the EU Clinical Trials Register, the European version of, had deposited their results within the required time period. Evidence from the United States suggests that almost a third of clinical trials do not post results to or publish them in a peer-reviewed journal within four years of completion. A more recent study found that less than 36% of studies conducted by academic medical centers reported their clinical trial results within two years of completion.

The Advantages of Being Compliant and Transparent

To help ensure that more trials register their results, the FDA recently released new draft guidance (pdf) that proposes to impose monetary penalties on clinical trial sponsors that do not post their clinical study results to These fines could add up to as much as $10,000 per day if results are not reported in a timely and appropriate manner. Notably, these regulations will require pharmaceutical companies to publish negative results, which is an important way of encouraging transparency by making it difficult to conceal unfavorable findings or present a misleading picture of the effectiveness of a product or drug.

Compliance with these new regulations has many advantages in addition to avoiding unnecessary monetary penalties. Increased registration is expected to help aid recruitment to clinical trials and minimize study duplication. In addition, making clinical study results available to the general public means that doctors and patients can make more informed decisions about treatment. From the perspective of pharmaceutical companies, transparency about negative results can increase trust from the public sector, boost employee morale, and help attract socially conscious investors; and having more information about competitors’ trials can improve competitive intelligence.

What This Means for You, and How We Can Help

The FDA welcomes feedback and comments on their draft guidance (pdf) for clinical trial transparency and the proposed monetary penalties. Review this guidance today, and consider having your company submit a formal response at

If you’re still unsure about whether your trial is in compliance with the new regulations, we can help! Our free TrialCompliance Lite tool enables you to search for any study to determine whether it complies with the current regulations. We also offer a full TrialCompliance service that compiles trial compliance data on a weekly basis and allows you to export and filter it in a number of useful ways.

Register today to access TrialCompliance Lite for free!


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