Scientists call for greater transparency in registered trials

5 MARCH 2009

Human Reproduction has today published an article in which leading endometriosis researchers call for investigators to disclose clinical trial data to the public within 12 months of a trial’s completion. According to the authors, such disclosure is the only moral and ethical thing to do – but they also argue that this is the only thing that makes sense scientifically and economically, if scientists are ever to crack the enigma that is currently endometriosis.

Picture of Professor Sun-Wei Guo
Professor Sun-Wei Guo, Shanghai Jiao Tong School of Medicine and Renji Hospital

Professor Guo and his co-authors found that 57 endometriosis-related trials had been registered, amongst which 25 were listed as completed and two as suspended. Yet, only three out of 15 completed phase II/III trials, which evaluated the efficacy of various promising compounds, have published their results. The remaining 12 (80%) of studies have so far not published their findings.

“This lack of transparency will not benefit trial sponsors nor the public, and will ultimately prove detrimental to research efforts attempting to develop more efficacious and safer therapeutics for endometriosis”, says Sun-Wei Guo, who is Professor and Director at the Institute of Obstetric and Gynaecologic Research at Shanghai Jiao Tong School of Medicine, and at Renji Hospital in China.

The authors followed up on the 1997 US Congress enacted section 113 of the Food and Drug Administration, which led to the creation of as a public depository for information on studies of drugs, including investigation on new treatments for endometriosis.

“The very purpose of mandatory registration is to make results of clinical trials public knowledge, including the good (efficacy) and the bad (lack of efficacy and/or adverse effects) results, so that everyone will benefit from hard-earned lessons so that positive results are built upon scientifically, and so that no one repeats others’ mistakes and miscalculations. Unless there is complete transparency some invaluable insight would be forever lost, along with their investment, to the detriment of the cause to uncover better therapeutics for endometriosis – and other conditions,” says Professor Guo.

Picture of Hans Evers
WES President, Professor Hans Evers, Maastricht University Hospital

World Endometriosis Society president and co-author, Professor Johannes Evers of Maastricht University in The Netherlands, expresses his concern about non-publication of clinical trial results:

“As clinicians and as scientists we must never lose sight of those brave women, who have placed themselves purposefully at risk by volunteering for clinical trials in the hope that a better treatment for endometriosis might be discovered.

We owe it to these volunteers to publish results of all trials, so that their participation results in knowledge that will be available to future patients and investigators to improve patient care,” says Professor Evers.


A call for more transparency of registered clinical trials on endometriosis. Guo S-W, Hummelshoj L, Olive DL, Bulun SE, D’Hooghe TM, and Evers JL.
Human Reproduction, 2009 doi:10.1093/humrep/dep045

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