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Clinical trials

The BMA is one of a number of prominent organisations calling for greater transparency in the reporting of clinical trial results.

Clinical research is essential for medical science to progress and to advance the treatment options available to patients.

The UK has excelled in this work to date and the BMA is keen for this to continue. For this to be the case, it is essential that patients and the public have confidence in those undertaking medical research and in the benefits of participating in clinical research.


How drugs are developed

The UK is the seventh largest pharmaceutical market in the world and one fifth of the world’s most popular prescription medicines are developed in the UK. For every marketed medicine that makes enough money to pay for its development, about 25,000 chemical compounds are tested, on average 25 of these will go into clinical trials and five will receive approval for marketing.

Clinical pharmacologists – working closely with basic research scientists, such as chemists, biochemists, pharmacologists and toxicologists – are involved with drug development, including tests on healthy volunteers or patients with the disease in question. Initial studies are usually undertaken on healthy volunteers to assess safety and tolerability and to examine a drug’s pharmacodynamic and pharmacokinetic profiles.

Drugs then go on to be studied in large multicentre trials (phase III) to evaluate their safety and efficacy. These studies form a key part of the clinical submission for international product registration. Since the establishment of NICE, these studies are often augmented by additional clinical research to generate supportive data with respect to the cost-effectiveness of a new drug.


Why all trial results matter

The under-reporting of these clinical trial results betrays the altruism of research subjects, risks the possibility that research will be repeated unnecessarily and could skew the evidence base for medical interventions that doctors rely on to prescribe safely and effectively for their patients.

The requirement to register trials and report results is enshrined in the World Medical Association Declaration of Helsinki. Despite this, estimates suggest that half of all trials have not been published and that trials which report positive results are twice as likely to be published as those with negative or no results.

In January 2014 MPs published a report calling on the Department of Health to ensure that full clinical trials data are made available for all treatments currently being prescribed in the UK. The Commons committee of public accounts said it was ‘surprised and concerned’ to discover that information about clinical trials was routinely withheld from doctors and researchers.

Find out more about the Commons committee's report on clinical trials data


The AllTrials campaign

The BMA is a signatory to the All Trials Registered, All Results Reported (AllTrials) initiative, which campaigns for greater transparency in clinical trials. At its 2013 Annual Representatives Meeting (ARM), the BMA also called on the Government to establish a mandatory open register for all trials and to make it compulsory for the results of all trials to be made public within a year of completion.

The ARM also clearly stated that selective non-publication of unflattering trial data is research misconduct and that registered medical practitioners who are believed to have been involved in such conduct should have their fitness-to-practise assessed by the GMC. 

Find out more about AllTrials

Find out more about the World Medical Association Declaration of Helsinki


Transparency measures in new EU Clinical Trials Regulation

In April 2014, the European Parliament agreed the final text of a new EU Clinical Trials Regulation. The regulation contains a number of provisions which represent an important step towards greater transparency of future clinical trials.

A new, publically accessible, clinical trials database is to be set up and administered by the European Medicines Agency. Sponsors are required to register a trial prior to its start, and any data in support of a trial application must come from a trial that is also registered in an accessible database or for which the results have been reported in an independent, peer-reviewed publication.

The regulation requires that both a summary and a lay summary of the results of a clinical trial are published within a year of a trial ending. If a clinical trial is intended to be used in an application to obtain a licence for a drug, the regulation also requires that the detailed clinical study report is made publically available through the database, three months after the application has been approved.

The data included in a clinical study report is not to be considered commercially confidential once the licence has been approved.