Background According to international consensus, an institutional review board (IRB) report is required prior to starting a clinical trial. The majority of clinical trial applications are rejected following initial IRB review. Modifications are needed to these applications prior to receiving IRB approval.

Purpose To evaluate the extent to which the onset of clinical trials are delayed due to IRB rejection during their initial review because of informed consent form (ICF) deficiencies, and to evaluate the types of objections to the ICFs.

Material and methods A retrospective observational study was performed following initial reviews of clinical trials conducted by the La Paz Hospital IRB (2012–2015). The primary endpoint was the number of clinical trials evaluated and rejected by the IRB following their initial review due to deficiencies observed in the trials’ ICFs and the type of objections appealed. Data were obtained from IRB meeting min during the study period.

Results Over the study period, 1858 clinical studies were evaluated. Of these, 1181 (63.5%) were rejected after the initial review. The objections leading to IRB rejection of a clinical study were due to defects in the ICFs (53.1%), design defects (27.4%) and other issues (30.5%). 1558 required a signed informed consent for subject participation (83.9%), of which 987 were not approved at first review because of objections to the informed consent documents (63.3%). The reasons for objections to the ICFs were primarily unreadability (11.7%) followed by inadequate information provided in accordance with Spain’s Data Protection Law, specifically regarding the rights that the data owner has to access his personal information, rectify it, cancel it or decline its use in the clinical study (9.2%), and biological sample management according to Spanish regulations (7.8%).

Conclusion Rejection of clinical studies by the IRB following their initial review was frequent and delayed the onset of these studies. Deficiencies found in studies’ ICFs were the main reason for research protocol rejections. There were two fundamental weaknesses in these documents: unreadability and discordance with different countries’ regulations, mainly concerning personal data protection and management of biological materials. Healthcare systems should promote integration and coordinate regulations to reduce diversity in legislation between countries to reduce waste in biomedical research.

References and/or acknowledgements La Paz Institutional Review Board members.

No conflict of interest