Clinical trials are human studies designed to evaluate the safety and efficacy of promising drugs, devices, procedures, or biologicals. In China, just as in western countries, regulatory agencies require scientific proof of the safety and efficacy of new drugs, devices, or procedures based on rigorous clinical trials before giving approval for marketing. These clinical trials are usually conducted in sequential phases. These phases are: preclinical (in vitro and animal studies, no human subjects involved), Phase 0 (very small size, for exploratory, first-in-human trials), Phase I (small in size, to evaluate safety and tolerance), Phase II (moderately sized, to evaluate safety as well as efficacy), Phase III (large in size, to evaluate mainly efficacy of the drug as compared with the existing “gold standard” treatment), and Phase IV (large in size, known as post-market surveillance trials for monitoring possible long-term adverse effects). Marketing approval requires favorable results from phase II trials. Although phase III trials are not necessary for regulatory approval in most cases, approval from agencies such as the Food and Drug Administration (FDA) of the USA and the European Medicines Agency (EMEA) of the EU requires at least two substantial Phase III trials.

 

Approximately a decade ago, most, if not all, clinical trials, mostly phases II and III, were shrouded with secrecy, in the name of proprietary or privileged rights. The public was kept in complete darkness, utterly unaware of their existence, let alone of any significant adverse effects of a trialed compound. Believing that this situation was not in the best interests of the American people and seeking to remedy this, the US Congress decided to encourage openness by enacting Section 113 of the Food and Drug Administration Modernization Act (FDAMA 113) in November 1997. Section 113 ultimately led to the creation of www.ClinicalTrials.gov as an Internet-based public depository for information on studies of drugs, including biological compounds, that are conducted under the FDA’s investigational-new-drug regulations . In September 2004, the International Committee of Medical Journal Editors (ICMJE) announced that its journals would not publish the results of any clinical trial that had not been appropriately registered at ClinicalTrials.gov or another qualified public registry by 13 September 2005. The ICMJE announcement prompted a surge of registrations at ClinicalTrials.gov, especially from industry.

 

Carrying on this trend of increased transparency, the World Health Organization (WHO) also launched a new web site in May 2007 that enables researchers, health practitioners, consumers, journal editors and reporters to search for information on clinical trials more easily and quickly. On 27 September 2007, the US Congress enacted the FDA Amendments Act of 2007 (FDAAA), or Public Law 110-85. On the same day, the FDA Revitalization Act was signed into law, which aims to improve the FDA’s ability to ensure the safety of the nation’s drugs and medical devices. Section 801 of FDAAA mandates the expansion of ClinicalTrials.gov and provides for the first federally funded trial results database. It also calls on the National Institutes of Health of US to augment ClinicalTrials.gov to include a ‘basic results’ database by September 2008. As specified by the law, the data elements include participant demographics and baseline characteristics, primary and secondary outcomes and statistical analyses and disclosure of agreements between sponsors and non-employees restricting researchers from disseminating results at scientific forums. A draft version of ‘Basic results’ data element Definitions, posted on 22 September 2008, at ClinicalTrials.gov lists ‘participant flow’, ‘arm/group’, ‘milestone(s)’, ‘reasons not completed’, ‘adverse event’, ‘baseline characteristics’, ‘baseline measure(s)’, ‘outcome measures’, ‘measure type’, ‘measure of dispersion’, ‘unit of measure’, ‘outcome data’ and ‘descriptive statistics’ as required data elements, and ‘statistical analyses’, ‘comparison group selection’, ‘statistical test of hypothesis’, ‘P-value’, ‘method’ and ‘method of estimation’ as conditionally required. These data elements collectively capture the essence of a clinical trial from design to end. Generally, these data will be available to the public within 12 months of trial completion or within 30 days of FDA approval (or clearance) of a new drug, biological or device. Clearly, the pressure is mounting for more transparency of all clinical trials, to the benefit of those who research disease pathogenesis, and ultimately to those who suffer from conditions such as cancer.

 

In China, an online clinical trial registry, Chinese Clinical Trial Register (sic) (www.chictr.org) was established following a meeting attended by participants from 48 medical and pharmaceutical journals, Chinese Evidenced-Based Medicine Centre of the Ministry of Health, Chinese Clinical Trial Register (sic), Chinese Cocherane Centre, and Ministry of Education Virtual Research Centre of Evidence-Based Medicine. Currently, 323 trials have been registered there (accessed on February 21, 2009). As stated, the registry emulates the WHO International Clinical Trials Registration Platform, and is under the auspices of the Chinese Clinical Trial Registration and Publishing Collaboration (ChiCTRPC) and maintained by the Chinese Evidenced-Based Medicine Centre of the Ministry of Health, Chinese Cocherane Centre, and Ministry of Education Virtual Research Centre of Evidence-Based Medicine. Starting from January 1, 2007, all member journals of the ChiCTRPC will prioritize the publication of clinical trial papers with a unique registration identifier, and gradually gravitate to publish only those trials.

 

Globally, the pressure for more transparency of clinical trials, is mounting. Gone is the era when nearly all trials were cloaked in secrecy.

 

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