In a newly published report, a group of researchers says one third of the clinical drug trial results federal regulators review in approving new drugs are not published and the researchers are pushing for all trial results to be made public.
The study, published in BMJ Open, grades drug companies on their transparency, the Washington Post reports. The researchers examined thousands of pages of regulatory documents, counting the number of trials Food and Drug Administration (FDA) regulators reviewed, versus how many trials were published or publicly reported.
The team organized their results in a transparency report card showing how much of the evidence about how 15 drugs approved in 2012 work in people was made publicly available. Jennifer Miller, an assistant professor of medical ethics at New York University School of Medicine, oversaw the research. She said this type of evidence is important in the practice of evidence-based medicine. “If the public evidence is partial or biased you risk having partial or biased [prescribing] guidelines,” according to the Post.
The study does have limitations: it analyzed only a subset of drugs approved in a single year, 2012. Further, the researchers looked only at whether clinical trials were registered and reported, not at the about how the drugs worked, the Post reports.
Clinical trials are normally conducted in three phases, with Phase III trials being the largest and most authoritative. Phase III trials test the safety and effectiveness of drugs. Under 2007 FDA requirements, later-stage trials meeting certain requirements are required to be reported and registered. Only a small fraction of the trials the study identified were required to be disclosed for each drug, but five drugs made by three companies were rated as zero percent compliant. Three of the 15 drugs studied had at least one publicly unavailable late-stage phase III trial, according to the Post.
The non-profit, Bioethics International, which is funded by foundations and universities but not pharmaceutical companies, will publicly grade the transparency of drug companies year by year, in a report card format. The researchers say a “Good Pharma Scorecard” will provide an added incentive for companies to be more transparent. The report card in the new study gave the companies a transparency grade, based on what percentage of all trial results, not just the ones required to be reported, were made publicly available.
Gilead’s HIV drug Stribild, a combination medication, received a grade of 21 percent. Of 34 trials presented to the FDA, 26 were never made public, according to the Post. Bayer’s drug for colorectal cancer, Stivarga, got 47 percent, with 7 of 12 trials not made public. Pfizer scored 100 percent for its kidney cancer drug, Inlyta. All 28 trials presented to the FDA were made public.
The researchers say selective evidence makes it more difficult for physicians to know how a drug works on patients. Unreported trials—usually the ones with inconclusive or negative findings—may contain information useful to physicians in their treatment decisions.
A 2008 study in the New England Journal of Medicine examined evidence provided to the FDA in support of a dozen antidepressants. Nearly two dozen studies that showed the drugs did not work were not published, the Post reports. Eleven others were “published in a way that, in our opinion, conveyed a positive outcome,” according to the study’s authors. Only three studies showing negative results were published. Overall, nearly a third of the studies submitted to the FDA were not published.