After an 18-month saga, the European Medicines Agency (EMA) has approved the details of a new system allowing researchers to scrutinize unpublished data from clinical trials. Scientists and transparency campaigners have praised the decision as a big step forward but have voiced lingering concerns, in particular about information that could be redacted before clinical study reports are shared.

EMA is the “first entity in the world” to introduce such rules, Executive Director Guido Rasi pointed out at an event in the European Parliament earlier this week, adding that the agency is “setting new standards for transparency.” The plan, which wasapproved yesterday at a managing board meeting in London, “represents a real shift in favour of ensuring research data is shared routinely and re-used effectively in the public interest,” agrees Carl Heneghan, director of the Centre for Evidence Based Medicine at the University of Oxford and co-founder of the AllTrials campaign, in a statement released yesterday.

EMA's decision is part of a major battle over who has the right to see and analyze the data from clinical studies of drugs, vaccines, and other medical products. Published journal articles often contain the main outcomes of such studies but lack detailed data and information about study design, efficacy, and safety analysis, which might shed a different light on the results when analyzed by others; moreover, some trials aren't published at all. The AllTrials campaign has argued that the details of every trial should be publicly available for anyone to study. Industry has balked at the idea, although some companies have recently committed to greater openness.

The new rules will apply to data submitted as part of marketing authorization applications after 1 January 2015. “Access to clinical data will allow third parties to verify the original analysis and conclusions, to conduct further analyses, and to examine the regulatory authority's positions and challenge them where appropriate,” the policy states. In return, the agency expects to receive a copy of the articles resulting from secondary analyses before publication, and says these should also be in the public domain.

To avoid interference with the regulators' decision-making, however, data will be shared only after the European Commission has reached a decision on a given application, “which implies a timeframe of about 18 months,” EMA says in an explanatory statement.

To the relief of outraged campaigners, the agency scrapped recent plans that allowed users to view data only on screen. Under the future system, scientists will be able to download, save, and print searchable clinical reports “for academic and other non-commercial research purposes,” while data will be available on screen only for all other users, after a simple registration process.

However, transparency campaigners are still concerned that the terms of use make individual researchers “vulnerable to protracted legal battles with large companies,” and that information can be blacked out before clinical study reports are shared. The policy's annex 3 lists items that could be redacted from clinical study reports because it may be considered “commercially confidential information.” This includes, for example, details about proprietary information about analytical methods, or so-called exploratory endpoints that could provide clues of potential off-label uses to competitors.

EMA expects that about 5% of a report's content could be removed in this way, Rasi said, adding that the final word on what gets redacted rests with the agency, even if the company disagrees. But “the list of factors that would justify the redaction is … way too expansive,” says Ilaria Passarani, head of the food and health department at the European consumers' organization BEUC in Brussels, in an e-mail to ScienceInsider. “EMA’s attitude to redactions should be independently audited to ensure overzealous approaches do not hinder access to important information,” Heneghan says.

The policy will be reviewed by June 2016 and will serve as a bridge until the rollout of the revamped E.U. clinical trial regulation—which provides a legal basis for the release of clinical trial results, but will enter into force no sooner than May 2016. (This means that results of the first trials conducted under the new law will be publicly available from 2019 or 2020 on.) At a later stage, EMA also plans to make available individual patient data.