Clinical trials are a key driver of medical innovation and progress. The medical community, the private sector, public bodies and patients should have unrestricted access to reliable information on clinical trials and on the benefits and harms of tested drugs, medical devices and treatments.

Clinical trial transparency, or the disclosure of clinical trial results and appropriate sharing of clinical trial data, is important for numerous reasons. Its value is recognised by many, not least by the World Health Organisation (WHO), that emphasises there is an ethical imperative to publicly share the results of all clinical trials, including those of unreported trials conducted in the past.

Another institution advocating for more transparency in clinical trials is the European Medicines Agency (EMA). In its ‘Policy on publication of clinical data for medicinal products for human use’ (Policy 0070), the agency mentions: "A high degree of transparency will take regulatory decision-making one step closer to EU citizens and promote the better-informed use of medicines. (…) The access to clinical data will benefit public health in the future."

Recently, the EU Clinical Trials Regulation was instated: it requires that European trials are registered before they begin, and that their results are reported within a year of trial end. The US has a similar law, that mandates that results from clinical trials are reported onto the register of the Food & Drug Administration (FDA), ClinicalTrials.gov, within the same timelines. But both initiatives are not enough.

Transparency is key

The benefits of sharing research data are undeniable: it improves the allocation of public health resources, and limits waste of research funds by avoiding unnecessary repetition of trials that have already been done without researchers’ knowledge.

This way, transparency leads to accelerated medical progress and the discovery of new treatments and cures. Moreover, it improves decision-making by clinicians as well as patients, because more reliable information is available to them - for the same reason, transparency protects the safety of patients by ensuring all potential harms are disclosed.

Or, the other way around: it may be clear that, when decisions are based on the results of only a subset of conducted clinical trials, poor allocation of resources for drug development, needless financing of available treatments, and suboptimal regulatory and public health recommendations will arise.

Patients have a right to know

Equally important is that all patients have the right to access scientifically sound information about their disease and treatment options. This allows them to participate in the decision-making process related to the management of their disease.

In our personal service for cancer patients, My Cancer Navigator, we aim to help patients by providing them with understandable and reliable information about their cancer and treatment, based on science. Of course publications and registries of ongoing clinical trials are two important resources for the scientists of My Cancer Navigator, in addition to the standard cancer specific guidelines.

Obviously, we can only provide information that is available to us, i.e publicly accessible. Unfortunately, available sources of information such as journal articles, clinical trial registries and information available from regulatory authorities, leave us with an incomplete overview of existing scientific research.

Patients with advanced cancer will often look for participation in a clinical trial, especially when the available options from the official treatment guidelines are exhausted. Information on which clinical trials could be an option, can be found on clinical trial registries (e.g. EudraCT, ClinicalTrials.gov). Theoretically that is - because not all trials are registered, and the information that is available is often incomplete or outdated.

Although the availability of the results of clinical trials are clearly crucial to inform patients, researchers and clinicians on experimental treatments, numerous past studies have shown that approximately half of all clinical trials that have been conducted and completed have never been published in academic journals. Adding to this, trials with positive results are twice as likely to be published as others.

Moving in the right direction

It's not all bad news: a recently published analysis shows that there is a significant improvement of clinical trial reporting in the recent years – at this point, around 80% of the drug trials have results available on the European trial registry, up from just 50% a few years ago.

However, let’s not forget that this means that still for 20% of the trials – this means over 3,300 European clinical trials in total – results remain unreported. The findings of many of these trials may never see the daylight unless made public in the foreseeable future.

As you would expect, in order to improve our service to patients and for the sake of patients in general, we want clinical trial transparency to be improved further.

We wrote our transparency policy

The Anticancer Fund has recently published its Clinical Trial Transparency policy on its website, providing a set of rules for clinical trials that we provide funding for.

Ideally, the following information is publicly available for each clinical trial:

• Registration of the trial on an official clinical trial registry: before the first patient receives the first medical intervention in the trial. The registry information must be updated as needed, for example to include final participant numbers and the date of completion.
   
• Results should be made public within a year after trial end, not only when a trial has positive results, but also, and maybe even more so, when a researched treatment strategy turns out to be unsuccessful. A summary of the results must be posted on the registry as soon as possible, followed by the much more detailed final study report, once ready.
   
• Apart from uploading the results to the registry, the results of a clinical trial should be published in a peer-reviewed journal. In order for a broader public to be able to read these scientific publications, submission to so called ‘open access’ journals should be encouraged - ‘Open access’ means that the article can be consulted at no cost.
   
• Raw data and individual patient data sharing: this is the most controversial topic, since it covers the sharing of the original dataset the analysis of the trial results was based on. Current barriers are issues with the protection of patients’ privacy, and on the other hand reluctancy of industry, that fears the sharing of these data will cause a competitive disadvantage. Nevertheless, re-use of the data by other researchers may increase the potential impact resulting from the initial trial.

What about the future?

Both in Europe and the US, the awareness of the importance of clinical trial transparency and the attention towards compliance with transparency rules is increasing.

The large number of clinical trials initiated by the ongoing COVID-19 pandemic and associated transparency efforts, contributed to this shift in attention. It is important not to lose the current momentum.

Although our Clinical Trial Transparency Policy may not be entirely enforceable, we see it as our mission to make at least our own funded trials as transparent as possible.

Because ultimately, it is the patient that will benefit. We hope that more organisations join us in advocating and invoking the transparency of clinical trials.

Further reading

WHO Statement on public disclosure of clinical trial results.

European Medicines Agency policy on publication of clinical data for medicinal products for human use.

European Code of Cancer Practice.

Clinical Trial Disclosure and Data Transparency: Obligation or Opportunity? Massimo Zaninelli, Robert Paarlberg, January 8, 2021.

Funders’ data-sharing policies in therapeutic research: A survey of commercial and non-commercial funders. Gaba JF, Siebert M, Dupuy A, Moher D, Naudet F (2020) PLOS ONE 15(8): e0237464.

Compliance with requirement to report results on the EU Clinical Trials Register: cohort study and web resource. Goldacre B, DeVito NJ, Heneghan C, et al. BMJ 2018;362:k3218