Publicising trial results before peer review

On 23 November 2018, Novo Nordisk issued a 500 word press release to report results of PIONEER 6, the cardiovascular outcome trial of oral semaglutide, an analogue of glucagon-like peptide 1 (GLP-1).1 We assume this study will soon be published in a peer reviewed journal, but in the meantime, the press release reported a “significant reduction in cardiovascular death and all-cause mortality.”

If supported by the trial data, this is undoubtedly an important development (the subcutaneous formulation, which the US Food and Drug Administration approved in 2017, has not been shown to improve all cause mortality). However, it is not possible to evaluate these claims with the limited information in the press release. Press releasing key results before peer reviewed publication is becoming increasingly common. The recent case of semaglutide offers an opportunity to examine the potential effect of these press releases—and reasons to remain sceptical until full trial results can be reviewed.

The press release’s declaration of improved cardiovascular and all cause mortality suggests an unequivocal and important benefit of oral semaglutide compared with placebo. Excitement …