According to reports from Swiss researchers, since 1 October 2025 there have been problems with new registrations and updates to existing registrations of clinical trials on clinicaltrials.gov due to the US government shutdown.

According to Art. 64 para. 4 of the Clinical Trials Ordinance (ClinO), an approved clinical trial must be registered in a WHO primary register before the trial is conducted and within six months of approval.

What can researchers do if problems with clinicaltrials.gov persist?

Instead of clinicaltrials.gov, other WHO-approved primary registries can be used for registration in accordance with Art. 64 para. 1 ClinO. For example, the following two registries allow English-language registrations of clinical trials taking place in Switzerland:

• ISRCTN (UK), registration subject to a fee (GBP 250)

• DRKS (Germany), registration free of charge, French or Italian authorisations from the relevant ethics committee may need to be translated into German or English

More information can be found, for example, in this article by the IQWiG and here.